Information recording medium, method for recording information, and method for reproduction information

ABSTRACT

An information recording medium includes a first area (DA 2 ) for storing picture data for forming a plurality of pictures, a second area (DA 21 ) which is included in the first area and stores control data of the picture data, and a third area (INFO 1 ) which is included in the second area and stores specifying data for specifying the storage position of representative picture data for forming a representative picture in the plurality of pictures.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a divisional of parent U.S. application Ser.No. 10/125,599, filed on Apr. 19, 2002, now U.S. Pat. No. 6,532,336which in turn is a divisional of grandparent U.S. application Ser. No.09/233,027, now U.S. Pat. No. 6,385,389, the entire contents of each ofwhich are hereby incorporated herein by reference.

BACKGROUND OF THE INVENTION

The present invention relates to an information recording medium such asa DVD (Digital Video Disk)-RAM (Random Access Memory) for recordingpredetermined information.

The present invention also relates to an information recording methodfor recording information on an information recording medium such as aDVD-RAM for recording predetermined information.

The present invention further relates to an information playback methodfor playing back information recorded on an information recording mediumsuch as a DVD-RAM for recording predetermined information.

In recent years, systems for playing back the contents of optical discsthat record video data (moving pictures), audio data, and the like havebeen developed, and have prevailed for the purpose of playing back moviesoftware titles, karaoke data, and the like as in LDs (laser discs),video CDs (video compact discs), and the like. Information aboutrecording contents such as titles is generally printed on the surfacesof such optical discs. Further, information about recording contentssuch as titles is generally added to the packages of these opticaldiscs. This allows the user to obtain the recording contents of anoptical disc without playing back the optical disc.

DVD standards that use MPEG2 (moving picture expert group) internationalstandards, and also use an audio compression scheme such as AC-3(digital audio compression), or the like, have been proposed. The DVDstandards include read-only DVD video (or DVD-ROM), write-once DVD-R,and recordable/readable DVD-RW (or DVD-RAM).

The DVD video (DVD-ROM) standards support MPEG2 as a moving picturecompression scheme, and AC-3 audio and MPEG audio in addition to linearPCM as audio recording schemes in accordance with the MPEG2 systemlayer. Furthermore, the DVD video standards are configured by addingsub-picture data obtained by runlength-compressing bitmap data forsuperimposed dialogs, and presentation control data (navigation data)for fast forward, rewind, data search, and the like. The standards alsosupport the UDF Bridge format (a hybrid of UDF and ISO9660) to allowcomputers to read data.

An optical disc currently used in DVD video (DVD-ROM) is a single-sided,single-layered 12 cm disc having a storage amount around 4.7 GB(gigabytes). A single-sided, two-layered disc has a storage amountaround 9.5 GB, and a double-sided, two-layered disc is capable ofrecording a large amount of data around 18 GB (when a laser of awavelength of 650 nm is used for reading).

An optical disc currently used in DVD-RW (DVD-RAM) is a 12 cm disc, andhas a storage amount of 2.6 GB (gigabytes) on one surface, i.e., 5.2 GBon the two surfaces. The currently available DVD-RAM optical disc has asmaller storage amount than that of a DVD-ROM disc of the correspondingsize. However, technical developments for expanding the amount of theDVD-RAM disc have been extensively made, and it is certain that aDVD-RAM disc having a storage amount more than 4.7 GB on one surfacewill be available in the near future.

However, since an MPEG2 video file that can obtain high picture qualityhas a large data size, the currently available DVD-RAM disc(single-sided 2.6 GB disc or double-sided 5.2 GB disc) does not alwayshave a sufficient recordable time (around 1 hour for 2.6 GB disc, around2 hours for 5.2 GB disc).

Since the user can freely record data on the DVD-RAM disc, noinformation representing recording contents is generally printed on thedisc surface. For the same reason, no information representing recordingcontents is generally printed on the package of the DVD-RAM disc.

To obtain the recording contents of the DVD-RAM disc at a glance at thedisc appearance, the user must perform the following process. Forexample, the user grasps recording contents recorded on the DVD-RAMdisc. The user creates information representing the recording contentsof the DVD-RAM disc. The user writes the information representing therecording contents of the DVD-RAM disc on the disc surface.Alternatively, the user may add information representing the recordingcontents of the DVD-RAM disc to the disc package.

Since no information about recording contents is printed on the DVD-RAMdisc, as described above, the user cannot obtain the recording contentsof the optical disc at a glance at the disc appearance.

To obtain the recording contents of the optical disc at a glance at theappearance of the DVD-RAM disc, the user must perform predeterminedprocessing for the disc.

BRIEF SUMMARY OF THE INVENTION

The present invention has been made to solve the above problems, and hasas its object to provide the following information recording medium,information recording method, and information playback method.

(1) There is provided an information recording medium which cancontribute to easy display of information about the recording contentsof the information recording medium without any playback and cumbersomeprocessing of the information recording medium (DVD-RAM disc).

(2) There are provided an information recording method and informationplayback method which can easily display information about the recordingcontents of an information recording medium without any playback andcumbersome processing of the information recording medium.

To achieve the above objects, the information recording medium,information recording method, and information playback method accordingto the present invention have the following arrangements.

(1) The information recording medium according to the present inventioncomprises a first area for storing picture data for forming a pluralityof pictures, a second area which is included in the first area andstores control data of the picture data, and a third area which isincluded in the second area and stores specifying data for specifying astorage position of representative picture data for forming arepresentative picture in the picture data.

(2) The information recording method according to the present inventioncomprises the first step of playing back an information recording mediumhaving a first area for storing picture data for forming a plurality ofpictures, a second area which is included in the first area and storescontrol data of the picture data, and a third area which is included inthe second area and stores specifying data for specifying a storageposition of representative picture data for forming a representativepicture in the picture data, and the second step of obtaining therepresentative picture data on the basis of the specifying data obtainedby playback in the first step, and printing out the representativepicture based on the obtained representative picture data.

(3) The information playback method according to the present inventioncomprises the first step of playing back an information recording mediumhaving a first area for storing picture data for forming a plurality ofpictures, a second area which is included in the first area and storescontrol data of the picture data, and a third area which is included inthe second area and stores specifying data for specifying a storageposition of representative picture data for forming a representativepicture in the plurality of pictures, and the second step of obtainingthe representative picture data on the basis of the specifying dataobtained by playback in the first step, and displaying the picture basedon the obtained representative picture data.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIG. 1 is a perspective view for explaining the structure of arecordable/readable optical disc (DVD-RAM or DVD-RW disc);

FIG. 2A is a view showing the state in which the optical disc shown inFIG. 1 is stored in a cartridge;

FIG. 2B is a view showing the schematic arrangement of recording trackson the data recording area of the optical disc shown in FIG. 1;

FIG. 3 is a view for explaining the hierarchical structure ofinformation (the contents of the data recording area or a volume spaceof DVD video) recorded on the optical disc in FIG. 1;

FIG. 4 is a view showing information included in a lead-in area;

FIG. 5 is a view showing information included in volume/file managementinformation;

FIG. 6 is a view for explaining information included in playback controlinformation;

FIG. 7 is a view for explaining information included in menu indexinformation;

FIG. 8 is a view for explaining information included in controlinformation and a video object;

FIG. 9 is a view for explaining the logical structure of information(lead-in area) recorded on the optical disc in FIG. 1;

FIG. 10 is a view for explaining the directory structure of information(data file) recorded on the optical disc in FIG. 1;

FIG. 11 is a view for explaining the hierarchical structure ofinformation included in video object set VTSTT_VOBS in FIG. 8;

FIG. 12 is a view for explaining the contents of packs in the lowermostlayer of the hierarchical structure in FIG. 11;

FIG. 13 is a view for explaining the contents of a PCI packet in FIG.12;

FIG. 14 is a view for explaining the contents of video managerinformation VMGI in FIG. 8;

FIG. 15 is a view for explaining the contents of video managerinformation management table VMGI_MAT in FIG. 14;

FIG. 16 is a view for explaining the contents of video title setinformation VTSI in FIG. 8;

FIG. 17 is a view for explaining the contents of video title setinformation management table VTSI_MAT in FIG. 16;

FIG. 18 is a view for explaining the contents of program chain generalinformation PGC_GI;

FIG. 19 is a block diagram for explaining the arrangement of anapparatus (DVD video recorder) for recording/playing back digital movingpicture information at a variable recording rate using the informationwith the structures described with reference to FIGS. 3 to 18 on thedisc in FIG. 1;

FIG. 20 is a view showing an example of a remote controller foroperating the DVD video recorder in FIG. 19;

FIG. 21 is a flow chart for explaining printing of information about therecording contents of the optical disc;

FIG. 22 is a view showing the state in which picture information isprinted on a label added to the optical disc and cartridge;

FIGS. 23A, 23B, and 23C are views showing the state in which amountinformation is printed on a label added to the cartridge;

FIGS. 24A and 24B are views showing the state in which rewrite countinformation is printed on a label added to the optical disc;

FIG. 25 is a view schematically showing a data structure recorded on theoptical disc in a modification;

FIG. 26 is a view for explaining the directory structure of the opticaldisc having the data structure shown in FIG. 25;

FIG. 27 is a view schematically showing a data structure in an AV file;

FIG. 28 is a view showing the recording location of a video object onthe optical disc;

FIG. 29 is a view schematically showing a data structure in anallocation map table;

FIG. 30 is a view schematically showing example 1 of the data structureof RTRW video manager information;

FIG. 31 is a view schematically showing example 2 of the data structureof RTRW video manager information;

FIG. 32 is a view schematically showing example 3 of the data structureof RTRW video manager information;

FIG. 33 is a view showing the schematic structure of data in PGC controlinformation; and

FIG. 34 is a view showing an example of playback of video data usingPGC.

DETAILED DESCRIPTION OF THE INVENTION

A digital information recording/playback system according to anembodiment of the present invention will be explained hereinafter withreference to the accompanying drawings.

As a typical embodiment of a digital information recording/playbacksystem according to the present invention, an apparatus whichrecords/plays back moving pictures encoded by MPEG2 at a variable bitrate, e.g., a DVD digital video recording, is known. (An example of theDVD digital video recorder will be described in detail layer).

FIG. 1 is a perspective view for explaining the structure of arecordable/readable optical disc 10 used in the DVD digital videorecorder.

As shown in FIG. 1, this optical disc 10 has a structure obtained byadhering a pair of transparent substrates 14 each having recording layer17 using adhesive layer 20. Each substrate 14 can be formed of a 0.6 mmthick polycarbonate film, and adhesive layer 20 can consist of a verythin (e.g., 40 μm thick) ultraviolet setting resin. When the pair of 0.6mm thick substrates 14 are adhered to each other so that their recordinglayers 17 contact each other on the surfaces of adhesive layer 20, a 1.2mm thick large-amount optical disc 10 is obtained.

Optical disc 10 has center hole 22, and clamp areas 24 used for clampingoptical disc 10 upon its rotation are formed around center hole 22 onthe two surfaces of the disc. Center hole 22 receives the spindle of adisc motor when optical disc 10 is loaded into a disc drive (not shown).Optical disc 10 is clamped at its clamp areas 24 by a disc damper (notshown).

Optical disc 10 has information areas 25 that can record video data,audio data, and other information around clamp areas 24 on its twosurfaces.

Each information area 25 has lead-out area 26 on its outer peripheryside, and lead-in area 27 on its inner periphery side that contactsclamp area 24. The area between lead-out and lead-in areas 26 and 27 isdefined as data recording area 28.

On recording layer (optical reflection layer) 17 of information area 25,a recording track is continuously formed in, e.g., a spiral pattern. Thecontinuous track is divided into a plurality of physical sectors, whichhave serial numbers. Various data are recorded on optical disc 10 usingthese sectors as recording units.

Data recording area 28 serves as an actual data recording area, andrecords video data (main picture data) such as a movie or the like,sub-picture data such as superimposed dialogs, menus, and the like, andaudio data such as words, effect sounds, and the like as similar pittrains (physical shapes or phase states that bring about change inoptical conditions).

When optical disc 10 is a double-sided recording RAM disc in which eachsurface has one recording layer, each recording layer 17 can be formedby three layers, i.e., by sandwiching a phase-change recording materiallayer (e.g., Ge₂Sb₂Te₅) between two zinc sulfide-silicon oxide(ZnS•SiO₂) mixture layers.

When optical disc 10 is a single-sided recording RAM disc in which eachsurface has one recording layer, recording layer 17 on the side ofread-out surface 19 can be formed by three layers including thephase-change recording material layer. In this case, layer 17 on theside opposite to read-out surface 19 need not be an informationrecording layer but may merely be a dummy layer.

When optical disc 10 is a one-side read type two-layered RAM/ROM disc,two recording layers 17 can comprise a single phase-change recordinglayer (on the side farther from read-out surface 19; read/write), and asingle semi-transparent metal reflection layer (on the side closer toread-out surface 19; read-only).

When optical disc 10 is a write-once DVD-R, a polycarbonate substrate isused, gold can be used as a reflection layer (not shown), and anultraviolet setting resin can be used as a protection layer (not shown).In this case, an organic dye is used in recording layer 17. As theorganic dyes, cyanine, squarilium, chroconic, and triphenylmenthanedyes, xanthene and quinone dyes (naphthoquinone, anthraquinone, and thelike), metal complex dyes (phthalocyanine, porphyrin, dithiol complex,and the like), and so forth can be used.

Data can be written on such DVD-R disc using a semiconductor laserhaving a wavelength of 650 nm and an output of about 6 to 12 mW.

When optical disc 10 is a one-side read type two-layered ROM disc, tworecording layers 17 can be comprised of a single metal reflection layer(on the side farther from read-out surface 19) and a singlesemi-transparent reflection layer (on the side closer to read-outsurface 19).

In case of read-only DVD-ROM disc 10, pit trains pre-formed by a stamperon substrate 14, and a reflection layer of, e.g., a metal, is formed onthat surface of substrate 14, which is formed with pit trains. Thereflection layer is used as recording layer 17. In such DVD-ROM disc 10,no grooves serving as recording tracks are especially formed, and thepit trains formed on the surface of substrate 14 serve as tracks.

In various types of optical discs 10 described above, read-only ROMinformation is recorded on recording layer 17 as an embossed patternsignal. By contrast, no such embossed pattern signal is formed onsubstrate 14 having read/write (or write-once) recording layer 17, and acontinuous groove is formed instead. A phase-change recording layer isformed on such groove. In case of a read/write DVD-RAM disc, thephase-change recording layer in land portions is also used forinformation recording in addition to the groove.

When optical disc 10 is of one-side read type (independently of one ortwo recording layers), substrate 14 on the rear side viewed fromread-out surface 19 need not always be transparent to the read/writelaser beam used. In this case, a label may be printed on the entiresurface of substrate 14 on the rear side.

A DVD digital video recorder (to be described later) can be designed toattain repetitive recording/repetitive playback (read/write) for aDVD-RAM disc (or DVD-RW disc), single recording/repetitive playback fora DVD-R disc, and repetitive playback for a DVD-ROM disc.

FIG. 2A is a view showing the state in which the optical disc shown inFIG. 1 is stored in a cartridge. FIG. 2B is a view showing the schematicarrangement of recording tracks on the data recording area of theoptical disc shown in FIG. 1.

When disc 10 is a DVD-RAM (or DVD-RW), disc 10 itself is stored incartridge 11 to protect its delicate disc surface. When DVD-RAM disc 10in cartridge 11 is inserted into the disc drive of a DVD video recorder(to be described later), the shutter of cartridge 11 opens, disc 10 isclamped by the turntable of a spindle motor (not shown) and rotated toface an optical head (not shown).

On the other hand, when disc 10 is a DVD-R or DVD-ROM, disc 10 itself isnot stored in cartridge 11, and bare disc 10 is directly set on the disctray of a disc drive.

Recording layer 17 of information area 25 shown in FIG. 1 is formed witha continuous data recording track in a spiral pattern. The continuoustrack is divided into a plurality of logical sectors (minimum recordingunits) each having a given storage amount, as shown in FIG. 2B, and dataare recorded with reference to these logical sectors. The recordingamount per logical sector is determined to be 2,048 bytes (or 2 kbytes)which are equal to one pack data length (to be described later).

Data recording area 28 is an actual data recording area, which similarlyrecords management data, main picture (video) data, sub-picture data,and audio data.

Note that data recording area 28 of disc 10 shown in FIG. 2A can bedivided into a plurality of ring-shaped (annular) recording areas (aplurality of recording zones), although not shown. The disc rotationalvelocity varies in units of recording zones. However, within each zone,a constant linear or angular velocity can be set. In this case, anauxiliary recording area (free space or area) can be provided for eachzone. These free spaces in units of zones may collectively form areserve area for that disc 10.

FIG. 3 to FIG. 11 are views for explaining the hierarchical structure ofinformation recorded on optical disc 10 shown in FIG. 1.

Data recording area 28 formed on optical disc 10 shown in FIG. 1 has astructure, as shown in FIG. 3. The logical format of this structure isdefined to comply with, e.g., the Universal Disk Format (UDF) Bridge (ahybrid of UDF and ISO9660) as one of standard formats.

Data recording area 28 between lead-in area 27 and lead-out area 26 isassigned as a volume space. Volume space 28 can include a space forinformation of the volume and file structures (volume/file managementinformation 70), and a space for the application of the DVD format (dataarea (rewritable) DA).

Volume space 28 is physically divided into a large number of sectors,and these physical sectors have serial numbers. The logical addresses ofdata recorded on this volume space (data recording area) 28 mean logicalsector numbers, as defined by ISO9660 and the UDF Bridge. The logicalsector size in this space is 2,048 bytes (or 2 kbytes) as the effectivedata size of the physical sector. The logical sector numbers areassigned serial numbers in ascending order of physical sector numbers.

Unlike the logical sectors, each physical sector is added with redundantinformation such as error correction information and the like. For thisreason, the physical sector size does not strictly match the logicalsector size.

That is, volume space 28 has a hierarchical structure, which includesvolume/file management information 70 and data area DA. These areasincluded in volume space 28 are split up on the boundaries of logicalsectors. Note that one logical sector is defined to be 2,048 bytes, andone logical block is also defined to be 2,048 bytes. Hence, one logicalsector is defined equivalently with one logical block.

Volume/file management information 70 corresponds to a management areadefined by ISO9660 and the UDF Bridge.

The embossed data area of lead-in area 27 records in advance informationabout the outline of the information recording medium, information aboutrecording, playback, and erase characteristics, and information aboutthe manufacture of the information recording medium. Information aboutthe outline of the information recording medium is information such asthe disc type (DVD-RAM, DVD-ROM, CD-ROM, or the like) of optical disc10, the disc size, the recording density, the physical sector numberrepresenting the recording start/recording end position, and the like.Information about recording, playback, and erase specifications isinformation such as the recording power, the recording pulse width, theerase power, the playback power, the recording/erase linear velocity,and the like. Information about the manufacture of the informationrecording medium is information such as the manufacturing number.

The rewritable areas of lead-in and lead-out areas 27 and 26 have uniquedisc name recording areas for identifying the information recordingmedium, test recording areas (for confirming recording/eraseconditions), and defective management information recording areas aboutdefective areas in data area DA. These areas allow recording by thedigital information recording/playback system.

Data area DA includes a data recording area for recording predetermineddata. Data area DA allows mixed recording of computer data, audio data,and video data. In this data area DA, the recording order and recordinginformation sizes of computer data, audio data, and video data can bearbitrarily set. In FIG. 3, areas which record computer data will becalled computer data areas DA1 and DA3, and an area which records audio& video data will be called audio & video data area DA2.

Audio & video data area DA2 records control information DA21, videoobject DA22, picture object DA23, and audio object DA24. Controlinformation DA21 is control information necessary for processes such aspicture recording (sound recording), playback, editing, and search.Video object DA22 is recording information (moving picture data) ascontents of video data. Picture object DA23 includes still pictures suchas slides and stills, information for searching video data for targetdata, and information about an edit thumbnail in video data. Audioobject DA24 is sound recording information as contents of audio data.

Control information DA21 includes playback control information DA211,recording control information DA212, edit control information DA213, andreduced drawing control information DA214. Playback control informationDA211 is control information necessary for playback. Recording controlinformation DA212 is control information necessary for recording(picture recording and sound recording). Edit control information DA213is control information necessary for editing. Reduced drawing controlinformation DA214 includes information for searching video data fortarget data, and management information about an edit thumbnail in videodata.

Reduced drawing control information DA214 includes anchor pointer DA2141and picture address table DA2142. Picture address table DA2142 recordsmenu index information INFO1, index picture information INFO2, slide &still picture information INFO3, information picture information INFO4,defective area information INFO5, and wallpaper picture informationINFO6.

Information included in lead-in area 27 will be described with referenceto FIG. 4.

The lead-in area 27 includes a data recording area for recording amountinformation 271. Amount information 271 has a data recording area forrecording total amount information 2711 and free area information 2712.Total amount information 2711 records the total amount of optical disc10. Free area information 2712 records a free area (remaining area) ofoptical disc 10. Note that total amount information 2711 and free areainformation 2712 are information to be printed, which will be describedin detail below. The hierarchical structure of lead-in area 27 will beexplained in more detail with reference to FIG. 9 to FIG. 11.

Information included in volume/file management information 70 will bedescribed with reference to FIG. 5.

Volume/file management information 70 includes a data recording area forrecording rewrite count information 701. Rewrite count information 701records the data rewrite count with respect to data area DA. Note thatrewrite count information 701 is information to be printed, which willbe described in detail below.

Information included in playback control information DA211 will bedescribed with reference to FIG. 6.

Playback control information DA211 includes a data recording area forrecording picture information INFO7. Picture information INFO7 isadditional data about moving picture data included in video object DA22.This additional data contains, e.g., recording date information INFO71,recording channel information INFO72, white balance information INFO73,zoom ratio information INFO74, shutter speed information INFO75, and GPSinformation INFO76. Note that these additional data are information tobe printed, which will be described in detail below.

Information included in menu index information INFO1 will be describedwith reference to FIG. 7.

Menu index information INFO1 includes data recording areas for recordingstart address data INFO11 and length data INFO12. Start address dataINFO11 is data representing the start of an address indicating thestorage location of representative picture data corresponding to arepresentative frame (to be described later). Length data INFO12 is datarepresenting a length from the address indicated by the start addressdata. This means that representative picture data is stored between theaddress indicated by start address data INFO11 and the addresscorresponding to the length indicated by length data INFO12. Acombination of start address data INFO11 and length data INFO12indicates the storage location of representative picture data.

Information included in control information DA21 and video object DA22will be described with reference to FIG. 8.

Referring to FIG. 8, video manager VMG consists of a plurality of files74A. These files 74A describe information (video manager informationVMGI, video object set VMGM_VOBS for video manager menus, and videomanager information backup file VMGI_BUP) for managing video title sets(VTS#1 to VTS#n) 72.

Each video title set VTS 72 stores video data (video pack to bedescribed later) compressed by MPEG, audio data compressed by apredetermined format or uncompressed audio data (audio pack),runlength-compressed sub-picture data (sub-picture pack to be describedlater; including bitmap data, each pixel of which is defined by aplurality of bits), and also information for playing back these data(navigation pack to be described later; including presentation controlinformation PCI and data search information DSI).

Video title set VTS 72 is also made up of a plurality of files 74B as invideo manager VMG. Each file 74B contains video title set informationVTSI, object set VTSM_VOBS for video title set menus, video object setsVTSTT_VOBS for video title set titles, and backup information VTSI_BUPfor video title set information.

Note that the number of video title sets (VTS#1 to VTS#n) 72 is limitedto a maximum of 99, and the number of files 74B that make up each videotitle set VTS 72 is limited to a maximum of 12. These files 74A and 74Bare similarly split up at the boundaries of logical sectors.

Other recording area 73 can record information that can be used in videotitle sets VTS 72 mentioned or other kinds of information that do notpertain to video title sets. This area 73 is not mandatory, and may bedeleted if it not used.

As will be described later with reference to FIG. 11, each video objectset VTSTT_VOBS for video title set titles defines a set of one or morevideo objects VOB. Each VOB defines a set of one or more cells. A set ofone or more cells make up program chain PGC.

Assuming that one PGC corresponds to one drama, a plurality of cellsthat make up this PGC can correspond to various scenes in that drama.The contents of the PGC (or those of cells) are determined by, e.g., asoftware provider who produces the contents recorded on disc 10.

FIG. 9 is a view for explaining information recorded on lead-in area 27of optical disc 10. When disc 10 is set in the DVD video recorder to bedescribed later (or DVD video player not shown), information on lead-inarea 27 is read first. Lead-in area 27 records a predetermined referencecode and control data in ascending order of sector numbers.

The reference code in lead-in area 27 is made up of two error correctioncode blocks (ECC blocks). Each ECC block consists of 16 sectors. Thesetwo ECC blocks (32 sectors) are created by adding scramble data. Uponplaying back the reference code added with the scramble data, filteroperation or the like on the playback side is done to play back aspecific data symbol (e.g., 172), thus assuring data read precisionafter that.

The control data in lead-in area 27 is made up of 192 ECC blocks. Thiscontrol data field repetitively records the contents for 16 sectors ineach block 192 times. First one sector (2,048 bytes) constituting thecontrol data (16 sectors) in lead-in area 27 contains physical formatinformation, and the subsequent 15 sectors contain disc manufacturinginformation and contents provider information.

The contents of the physical format information will be described.

The first byte position “0” describes the version of the DVD format thatthe recorded information complies with.

The second byte position “1” describes the size (12 cm, 8 cm, or thelike) of a recording medium (optical disc 10) and minimum read-out rate.In case of a read-only DVD video, 2.52 Mbps, 5.04 Mbps, and 10.08 Mbpsare prescribed minimum read-out rates, but other minimum read-out ratesare reserved. For example, when a DVD video recorder capable of variablebit rate recording records at an average bit rate of 2 Mbps, the minimumread-out rate can be set to fall within the range from 1.5 to 1.8 Mbpsusing the reserve field.

The third byte position “2” describes the disc structure (the number ofrecording layers, track pitch, recording layer type, and the like) ofthe recording medium (optical disc 10). Based on this recording layertype, disc 10 can be identified to be a DVD-ROM, DVD-R, or DVD-RAM (orDVD-RW).

The fourth byte position “3” describes the recording density (lineardensity & track density) of the recording medium (optical disc 10). Thelinear density indicates the recording length per bit (0.267 μm/bit,0.293 μm/bit, or the like). On the other hand, the track densityindicates the neighboring track spacing (0.74 μm/track, 0.80 μm/track,or the like). The fourth byte position “3” also includes a reserve fieldto designate other numerical values as the linear density and trackdensity of a DVD-RAM or DVD-R.

The fifth byte position “4 to 15” describes the start and end sectornumbers of data area 28 and the like of the recording medium (opticaldisc 10).

The sixth byte position “16” describes a burst cutting area (BCA)descriptor. This BCA is applied as an option to a DVD-ROM disc alone,and is an area for storing recorded information upon completion of thedisc manufacturing process.

The seventh byte position “17 to 20” describes a free space or free areaof the recording medium (optical disc 10). For example, when disc 10 isa single-sided recording DVD-RAM disc, information indicating 2.6 GB (orthe number of sectors corresponding to this number of bytes) is storedat that position of disc 10. On the other hand, when disc 10 is adouble-sided recording DVD-RAM disc, information indicting 5.2 GB (orthe number of sectors corresponding to this number of bytes) is storedat that position.

The eighth and ninth byte positions “21 to 31” and “32 to 2,047” arereserved for the future.

FIG. 10 exemplifies the directory structure of information (data files)recorded on optical disc 10. As in the hierarchical file structure usedby a versatile operation system of a computer, the subdirectory of videotitle set VTS and that of audio title set ATS are made under the rootdirectory. Various video files (files VMGI, VMGM, VTSI, VTSM, VTS, andthe like) are allocated in the subdirectory of video title set VTS tomanage the individual files systematically. A specific file (e.g.,specific VTS) can be accessed by designating the path from the rootdirectory to that file.

DVD-RAM (DVD-RW) disc 10 or DVD-R disc 10 shown in FIG. 1 may bepre-formatted to have the directory structure shown in FIG. 10, andpre-formatted discs 10 may be put on the market as unused discs (rawdiscs) for DVD video recording.

That is, the root directory of pre-formatted raw disc 10 includes asubdirectory named a video title set (VTS). This subdirectory cancontain various management data files (VIDEO_TS.IFO, VTS_01_0.IFO);backup files (VIDEO_TS.BUP, VTS_01_0.BUP) for backing up information ofthese management data files; and a video data file (VTS_01_1.VOB) whichis managed based on the contents of the management data files and storesdigital moving picture information.

The subdirectory can also contain menu data files (VMGM, VTSM) forstoring predetermined menu information.

The contents of a directory record corresponding to the directorystructure shown in FIG. 10 will be described.

The first relative byte position “0” describes the directory recordlength.

The second relative byte position “1” describes the record length of anassigned extent attribute.

The third relative byte position “2” describes the first logical sectornumber assigned to an extent.

The fourth relative byte position “10” describes the data length of thefile field.

The fifth relative byte position “18” describes the recording data/timeof information in the extent described in the directory record. Data atthe relative byte position “18” can be used for recording the recordingdata/time of a recorded program (corresponding to specific VTS) in theDVD video recorder.

The sixth relative byte position “25” describes a file flag indicatingthe characteristics of files defined in Table 10 of ISO9660.

The seventh relative byte position “25” describes the file unit sizeassigned to the file field.

The eighth relative byte position “27” describes the interleaved gapsize assigned to the file field.

The ninth relative byte position “28” describes the volume sequencenumber in the volume set on the extent described in the directoryrecord.

The 10th relative byte position “32” describes the file ID field lengthof the directory record.

The 11th relative byte position “33” describes the file ID or thedirectory defined by ISO9660.

Next to the file ID, a padding field serving as stuffing when the fileID field has an even-byte length is described.

Next to the padding field, copyright management information used by thesystem is described.

After the copyright management information, a read flag (or played backflag) indicating whether or not a specific recorded file (e.g.,VTS_01_1.VOB in FIG. 10) has been read out once (or that VTS has beenplayed back at least once previously) is described. The read flag for afile which is not yet read out is set at “0”. If the file has been readout at least once, the read flag of that file is set at “1”.

Next to the read flag, an archive flag (or permanent keep flag)indicating whether or not a specific recorded file (e.g., VTS_01_1.VOBin FIG. 10) has contents to be kept permanently (or contents that areprevented from being erroneously erased or deleted) is described. Thearchive flag for a file which can be erased is set at “0”. The archiveflag for a file which is to be kept permanently without being erased isset at “1”.

FIG. 11 shows the hierarchical structure of information contained invideo object set VTSTT_VOBS shown in FIG. 8.

As shown in FIG. 11, each cell 84 consists of one or more video objectunits (VOBU) 85. Each video object unit 85 is constituted as a set (packsequence) of video packs (V packs) 88, sub-picture packs (SP packs) 90,and audio packs (A packs) 91 to have navigation pack (NV pack) 86 at thebeginning of the sequence. That is, video object unit VOBU 85 is definedas a set of all packs recorded from certain navigation pack 86 to a packimmediately before the next navigation pack 86.

Each of these packs serves as a minimum unit for data transfer. Theminimum unit for logical processing is a cell, and logical processing isdone in units of cells.

Navigation pack 86 is built in each video object unit VOBU 85 to realizeboth angle changes (non-seamless playback and seamless playback).

The playback time of video object unit VOBU 85 corresponds to that ofvideo data made up of one or more picture groups (groups of pictures; tobe abbreviated as GOPs) included in video object unit VOBU 85, and isset to fall within the range from 0.4 sec to 1.2 sec. One GOP is screendata which normally has a playback time of about 0.5 sec in the MPEGformat, and is compressed to play back approximately 15 images duringthis interval.

When video object unit VOBU 85 includes video data, a video datastreamis formed by arranging GOPs (complying with MPEG) each consisting ofvideo packs 88, sub-picture packs 90, and audio packs 91. However,independently of the number of GOPs, video object unit VOBU 85 isdefined with reference to the playback time of GOPs, and navigation pack86 is always set at the beginning of unit 85, as shown in FIG. 11.

Even playback data consisting of audio data and/or sub-picture dataalone is formed using video object unit VOBU 35 as one unit. Forexample, when video object unit VOBU 85 is formed by audio packs 91alone to have navigation pack 86 at its beginning, audio packs 91 to beplayed back in the playback time of video object unit VOBU 85 to whichthe audio data belong are stored in that video object unit VOBU 85 as invideo object VOB 83 of video data.

When a DVD video recorder can record video title set VTS containingVOBSs 82 with the structure shown in FIG. 11 on optical disc 10, theuser often wants to edit the recording contents after the VTS isrecorded. In order to meet such requirement, dummy packs 89 can beappropriately inserted in each VOBU 85. Each dummy pack 89 can be usedfor recording edit data later.

As shown in FIG. 11, video object set (VTSTT_VOBS) 82 is defined as aset of one or more video objects (VOB) 83. Video objects VOB 83 in videoobject set VOBS 82 are used for the same purpose.

VOBS 82 for menus normally consists of one VOB 83, which stores aplurality of menu screen display data. By contrast, VOBS 82 for a titleset normally consists of a plurality of VOBs 83.

Taking a concert video title of a certain rock band as an example, VOBs83 that form video object set VTSTT_VOBS 82 for a title set correspondto picture data of the performance of that band. In this case, bydesignating given VOB 83, for example, the third tune in the concert ofthe band can be played back.

VOB 83 that forms video object set VTSM_VOBS for menus stores menu dataof all the tunes performed in the concert of the band, and a specifictune, e.g., an encore, can be played back according to the menu display.

Note that one VOB 83 can form one VOBS 82 in a normal video program. Inthis case, a single video stream comes to an end in one VOB 83.

On the other hand, in case of a collection of animations having aplurality of stories or an omnibus movie, a plurality of video streams(a plurality of video chains PGC) can be set in single VOB 82 incorrespondence with the respective stories. In this case, the individualvideo streams are stored in corresponding VOBs 83. An audio stream andsub-picture stream pertaining to each video stream end in correspondingVOB 83.

VOBs 83 are assigned identification numbers (IDN#i; i=0 to i), and thatVOB 83 can be specified by the identification number. VOB 83 consists ofone or more cells 84. A normal video stream consists of a plurality ofcells, but a video stream for menus often consists of single cell 84.Cells 84 are assigned identification numbers (C_IDN#j) as in VOBs 83.

FIG. 12 exemplifies a data sequence (pack sequence) in the pack format,which is obtained after data recorded on optical disc 10 are read out,and are subjected to signal demodulation/error correction in a discdrive (not shown). This pack sequence includes navigation pack (controlpack) 86, video packs 88, dummy packs 89, sub-picture packs 90, andaudio packs 91. All these packs consist of data in units of 2 kbytes asin the logical sectors shown in FIG. 2B.

Navigation pack 86 includes pack header 110, playback controlinformation/presentation control information (PCI) packet 116, and datasearch information (DSI) packet 117. PCI packet 116 is made up of packetheader 112 and PCI data 113, and DSI packet 117 of packet header 114 andDSI data 115. PCI packet 116 contains control data used upon switchingthe non-seamless angles, and DSI packet 117 contains control data usedupon switching the seamless angles.

Note that the angle switching means changes in angle (camera angle) ofwatching the object picture. In case of a rock concert video title, forexample, the user can watch scenes from various angles, e.g., a scenethat mainly captures a vocalist, a scene that mainly captures aguitarist, a scene that mainly captures a drummer, and the like in aperformance scene of an identical tune (identical event).

The angle is switched (changed) when the viewer can select angles inaccordance with his or her favor, and when an identical sceneautomatically repeats itself with different angles in the flow of story(if the software producer/provider has programmed the story in such way;or if the user of the DVD video recorder edits in such way).

The angles are set in the following cases: temporally discontinuous,non-seamless playback that presents and identical scene of differentangles (for example, in a scene at the instance when a certain boxerthrows a counter punch, the camera angle is changed to another angle toplay back a scene in which the counterpunch begins to be thrown), andtemporally continuous, seamless playback that changes the angle betweentemporally continuous scenes (for example, at the instance when acertain boxer has made a counterpunch, the camera angle is changed toanother angle to play back a scene in which the other boxer who got thepunch is blown off).

Video pack 88 is comprised of pack header 881 and video packet 882.Dummy pack 89 is comprised of pack header 891 and padding packet 890,and padding packet 890 of packet header 892 and padding data 893. Notethat padding data 893 stores insignificant data.

Sub-picture pack 90 is made up of pack header 901 and sub-picture packet902. Audio pack 91 is made up of pack header 911 and audio packet 912.

Note that video packet 882 in FIG. 12 contains a packet header (notshown), which records a decode time stamp (DST) and presentation timestamp (PTS). Each of sub-picture packet 902 and audio packet 912contains a packet header (not shown), which records a presentation timestamp (PTS).

Subsequently, the data structure for one navigation pack will bedescribed.

More specifically, one navigation pack 86 consists of 2,010 bytenavigation data including 14 byte pack header 110, 24 byte system header111, and two packets (116, 117). The two packets that form thenavigation data are presentation control information (PCI) packet 116and data search information (DSI) packet 117 in the description of FIG.12.

PCI packet 116 consists of 6 byte packet header 112A, 1 byte substreamidentifier (substream ID) 112B, and 979 byte PCI data 113. Thedatastream of PCI data 113 is designated by an 8 bit code “00000000” ofsubstream ID 112B.

DSI packet 117 is constructed by 6 byte packet header 114A, 1 bytesubstream identifier (substream ID) 114B, and 1,017 byte DSI data 115.The datastream of DSI data 115 is designated by an 8 bit code “00000001”of substream ID 114B.

The data length for one navigation pack 86 with the above structure is2,048 bytes (2 kbytes) corresponding to one logical sector shown in FIG.2B.

Pack header 110 and system header 111 are defined by the MPEG2 systemlayer. More specifically, pack header 110 stores information such as apack start code, system clock reference (SCR), and multiplexing rate,and system header 111 describes a bit rate and stream ID. Likewise,packet header 112A of PCI packet 116 and packet header 114A of DSIpacket 117 each store a packet start code, packet length, and stream ID,as defined by the MPEG2 system layer.

The structure for one dummy pack will be described. That is, one dummypack 89 is made up of pack header 891, packet header 892 with apredetermined stream ID, and padding data 893 padded with apredetermined code. (Packet data 892 and padding data 893 form paddingpacket 890). The contents of padding data 893 in a non-used dummy packare not especially significant. This dummy pack 89 can be appropriatelyused when the recording contents are to be edited after predeterminedrecording is done on disc 10.

For example, a case will be examined below wherein the contents of avideo tape that recorded a family trip using a portable video camera arerecorded and edited on DVD-RAM (or DVD-RW) disc 10.

In this case, only the video scenes to be stored in a single disc areselectively recorded on disc 10. These video scenes are recorded invideo pack 88 shown in FIG. 11. Also, audio data simultaneously recordedby the video camera is recorded in audio pack 91.

Each VOBU 85 that includes video pack 88 and the like has navigationpack 86 at its beginning. As shown in FIG. 12, this navigation pack 86contains presentation control information PCI and data searchinformation DSI. Using this PCI or DSI, the playback procedure of eachVOBU can be controlled (for example, discontinuous scenes can beautomatically connected or a multiangle scene can be recorded).

After the contents of the video tape are edited and recorded on disc 10,when a voice, effect sound, and the like are to be postrecorded (orafter-recorded) in each scene in units of VOBU or a background music(BGM) is added, such postrecording (or after-recording) audio data orBGM can be recorded in dummy pack 89. When a comment for the recordedcontents is to be added, sub-pictures such as additional characters,figures, and the like can be recorded in dummy pack 89. Furthermore,when an additional video picture is to be inserted, the inserted videopicture can be recorded in dummy pack 89.

The above-mentioned postrecording (or after-recording) audio data or thelike is written in padding data 893 of dummy pack 89 used as an audiopack. The additional comment is written in padding data 893 of dummypack 89 used as a sub-picture pack. Similarly, the inserted videopicture is written in padding data 893 of dummy pack 89 used as a videopack. Incidentally, when the postrecording (after-recording) ispredetermined, silent audio data coded in the same manner as theoriginal audio data can be written in the dummy pack. In this case, theoriginal audio data may be recorded as a first stream, and the silentaudio data may be recorded as a second stream.

More specifically, dummy pack 89 is a wildcard pack that can become anyof an audio, sub-picture, and video packs depending on its purpose.

FIG. 13 shows PCI packet 116 included in navigation pack 86 located atthe beginning of each VOBU 85. As shown in FIG. 13, PCI packet 116includes presentation control information PCI (PCI data) 113 asnavigation data used for changing the display or playback contents(presentation contents) in synchronism with the playback state of videodata in video object unit (VOBU) 85.

The contents of presentation control information (PCI data) 113 will bedescribed. PCI data 113 includes 60 byte PCI general information(PCI_GI), 36 byte non-seamless playback angle information (NSML_AGLI),694 byte highlight information (HLI), and 189 byte recording information(RECI). This recording information (RECI) can contain a copyrightmanagement code (ISRC) of the international standard.

Highlight information HLI is used upon execution of the followinghighlight processing. More specifically, the MPU (or CPU) of the DVDvideo recorder be described later) reads highlight information HLI, anddetects the X-/Y-coordinate values, colors, contrast values, and thelike of rectangular regions (highlight buttons) displayed by sub-picturedata. The MPU of the DVD video recorder highlights the displayed menuselection item and the like in accordance with these detected data. Thishighlight processing is used as a means for allowing the user to easilyrecognize a specific displayed item on the visual user interface. Morespecifically, when a D video title recorded on optical disc 10 is amultilingual compatible program, a specific spoken language (e.g.,English) and a specific superimposed dialogue language (e.g., Japanese)are selected by highlight buttons which are displayed to be visuallyoutstanding by the highlight processing.

The contents of general information PCI_GI of this PCI will bedescribed.

Presentation control information general information PCI_GI describesthe logical block number (NV_PCK_LBN) of a navigation pack, the category(VOBU_CAT) of a video object unit (VOBU), user operation control(VOBU_UOP_CTL) of the video object unit (VOBU), the start presentationtime (VOBU_S_PTM) of the video object unit (VOBU), the end presentationtime (VOBU_E_PTM) of the video object unit (VOBU), the end presentationtime (VOBU_SE_PTM) of the sequence in the video object unit (VOBU), anda cell elapse time (C_ELTM).

Note that the logical block number (NV_PCK_LBN) represents the address(recording location) of a navigation pack including the presentationcontrol information (PCI) by the relative number of blocks from thefirst logical block in the video object set (VOBS) which includes thatPCI.

The category (VOBU_CAT) describes the contents of copy protection of ananalog signal corresponding to video and sub-picture data in the videoobject unit (VOBU) that includes the presentation control information(PCI).

The user operation control (VOBU_UOP_CTL) describes user operationswhich are prohibited during the display (presentation) period of thevideo object unit (VOBU) that includes the presentation controlinformation (PCI).

The start presentation time (VOBU_S_PTM) describes the start time ofdisplay (presentation) of the video object unit (VOBU) that includes thepresentation control information (PCI). More specifically, thisVOBU_S_PTM indicates the start display time of the first video (firstpicture) in the display order of the first GOP in the video object unit(VOBU).

The end presentation time (VOBU_E_PTM) describes the end time of display(presentation) of the video object unit (VOBU) that includes thepresentation control information (PCI). More specifically, when thevideo object unit (VOBU) includes continuous video data, this VOBU_E_PTMindicates the end display time of the last video (last picture) in thedisplay order of the last GOP in the video object unit (VOBU).

On the other hand, when no video data is present in the video objectunit (VOBU), or when playback of that video object unit (VOBU) isstopped, this VOBU_E_PTM indicates the end time of virtual video dataaligned to the time grids at a field interval ( 1/60 sec in case of NTSCvideo).

The end presentation time (VOBU_SE_PTM) describes the end time ofdisplay (presentation) based on a sequence end code in video data in thevideo object unit (VOBU) that includes the presentation controlinformation (PCI). More specifically, this end time indicates the enddisplay time of the last video (last picture) in the display order,which picture includes the sequence end code, in the video object unit(VOBU). If no video (picture) with a sequence end code is present in thevideo object unit (VOBU), 00000000 h (h is an abbreviation forhexadecimal) is set in VOBU_SE_PTM.

The cell elapse time (C_ELTM) describes the relative display(presentation) time from the first video frame in the display order of acell that includes the presentation control information (PCI) to thefirst video frame in the display order of the video object unit (VOBU)that includes the PCI in hours, minutes, and seconds in the BCD formatand frames. When no video data is present in the video object unit(VOBU), the first video frame of the virtual video data is used as thevideo frame.

FIG. 14 shows the contents of video manager VMG shown in FIG. 8. ThisVMG consists of a plurality of files 74A. Video manager VMG includesvideo manager information (VMGI) 75, object set (VMGM_VOBS) for videomanager menus, and backup (VMGI_BUP) of video manager information incorrespondence with each file.

Note that video manager information VMGI and backup VMGI_BUP of videomanager information are mandatory items, and video object set VMGM_VOBSfor displaying video manager information menu VMGM is optional.

As shown in FIG. 14, video manager information (VMGI) 75 set at thebeginning of video manager VMG describes a video manager informationmanagement table (VMGI_MAT; mandatory), title search pointer table(TT_SRPT; mandatory), video manager menu program chain information unittable (VMGM_PGCI_UT; mandatory when VMGM_VOBS exists), parentalmanagement information table (PTL_MAIT; option), video title setattribute table (VTS_ATRT; mandatory), text data manager (TXTDT_MG;option), video manager menu cell address table (VMGM_C_ADT; mandatorywhen VMGM_VOBS exists), and video manager menu video object unit addressmap (VMGM_VOBU_ADMAP; mandatory when VMGM_VOBS exists) in this order.

Note that the addresses such as an end address (VMGI_MAT_EA) of videomanager information management table VMGI_MAT, a start address(TT_SRPT_SA) of title search pointer TT_SRPT, and the like are describedas the relative number of logical blocks from the head logical blockthat stores this table VMGI_MAT.

Video manager information (VMGI) 75 contains information used uponplaying back each video title set (VTS) 72 shown in FIG. 8, and suchinformation is recorded on optical disc 10 to match the logical sectorboundary.

Video manager information menu video object set VMGM_VOBS stores menuinformation (managed by video manager VMG) which pertains to video data,audio data, and sub-picture data recorded on optical disc 10.

With this video manager information menu video object set (VMGM_VOBS),the volume name of the optical disc to be played back, and audio andsub-picture comments upon displaying the volume name can be displayed.Also, selectable items can be displayed as sub-picture data.

For example, video manager information menu video object set (VMGM_VOBS)allows to display a comment indicating that the optical disc to beplayed back contains a video (in a single story or multi-story format)of the road to the world champion of given boxer X as sub-picture data.That is, the fighting pose of boxer X is played back as video datatogether with the volume name such as “glorious history of boxer X” orthe like, high theme (if any) is output as audio data, and thechronological table of his career/records and the like are displayed assub-picture data.

Also, as the selection items displayed as sub-picture data by VMGM videoobject set (VMGM_VOBS), (1) an inquiry as to whether a narration voiceof the match is played back in English, Japanese, French, German, andthe like, (2) an inquiry as to whether or not a superimposed dialog in apredetermined language is displayed as sub-picture data, and (3) aninquiry as to which one of a plurality of selectable languagesuperimposed dialogs is selected, are output. The viewer (the user ofthe DVD video recorder; to be described later) can select English as thenarration voice and Japanese as the sub-picture superimposed dialog fromthe displayed items by the VMGM video object set (VMGM_VOBS). In thisway, the user is ready to watch the video of the match of boxer X.

The above-mentioned features such as comments of the recording contentsusing sub-picture data and/or audio data, arbitrary selection of aspoken language and superimposed dialog language, and the aforementionedplayback angle changes are not available in a conventional videorecorder (VHS VCR or the like), but the DVD video recorder of thepresent invention can have such features.

FIG. 15 shows the contents of video manager information management tableVMGI_MAT shown in FIG. 14.

More specifically, video manager information management table VMGI_MATdescribes a video manager identifier (VMG_ID); the end address (VMG_EA)of the video manager; the end address (VMGI_EA) of video managerinformation; a version number (VERN) of the format that optical disc(DVD disc) 10 of interest uses; a video manager category (VMG_CAT); avolume set identifier (VLMS_ID); free space (recordable amount)FREE_SPACE of optical disc 10 on which video title sets VTS shown inFIG. 8 are recorded; the number of videotitle sets (VTS_Ns); a provider(a software producer/distributor) unique identifier (PVR_ID); the endaddress (VMGI_MAT_EA) of the video manager information management table;the start address (FP_PGCI_SA) of first play program chain information;the start address (VMGM_VOBS_SA) of the video manager menu video objectset; the start address (TT_SRPT_SA) of the title search pointer table;the start address (VMGM_PGCI_UT_SA) of the video manager menu programchain information unit table; the start address (PTL_MAIT_SA) of theparental management information table; the start address (VTS_ATRT_SA)of the video title set attribute table; the start address (TXTDT_MG_SA)of the text data manager; the start address (VMGM_C_ADT_SA) of the videomanager menu cell address table; the start address (VMGM_VOBU_ADMAP_SA)of the video manager menu video object unit address map; a videoattribute (VMGM_V_ATR) indicated by the video manager menu; the numberof audio streams (VMGM_AST_Ns) indicated by the video manager menu; anaudio stream attribute (VMGM_AST_ATR) indicated by the video managermenu; the number of sub-picture streams (VMGM_SPST_Ns) indicated by thevideo manager menu; a sub-picture stream attribute (VMGM_SPST_ATR)indicated by the video manager menu; and first play program chaininformation (FP_PGCI).

Note that video manager category VMG_CAT of video manager informationmanagement table VMGI_MAT describes video copy flags and audio copyflags of the video manager and video title sets. Depending on thecontents of these flags, whether or not video and audio data can becopied are independently determined.

Free space (recordable amount) FREE_SPACE shown in FIG. 15 equals freespace data in the physical format information. The free space of disc 10may be stored in either a file descriptor (physical format information)or management information (VMGI_MAT). The disc free space after disc 10is partially recorded can be written in FREE_SPACE in FIG. 15 and/or thefree space field of the physical format information (in this case, thatdata is written in both FREE_SPACE and physical format information).

For example, in case of single-sided DVD-RAM disc 10 having a storageamount of 2.6 GB, information indicating 2.6 GB is written in the freespace of the physical information. If no data is recorded on this disc10 at all, information indicating a value obtained by subtractingmanagement data (including video manager VMG) and the like from 2.6 GBis written in FREE_SPACE in FIG. 15.

If recording for 1 GB has been done on this disc 10, information storedin the free space field of the physical format information is equivalentto 2.6 GB, but information in FREE_SPACE in FIG. 15 is rewritten to thatindicating 1.6 GB or equivalent. When such partially recorded disc 10 isset in the DVD video recorder (to be described later), the DVD videorecorder initially reads the information in the free space field of thephysical format information to detect that set disc 10 is a 2.6 GB disc,and then reds the information in FREE_SPACE in FIG. 15 to detect thatthe free space of set disc 10 is 1.6 GB. If all the data on this disc 10are erased, the contents of FREE_SPACE in FIG. 15 and information in thefree space field of the physical format information in FIG. 15 arerewritten to indicate 2.6 GB or equivalent.

That is, upon expressing “free space”, the free space field of thephysical format information and FREE_SPACE in FIG. 15 can have differentcontents.

FIG. 16 shows the contents of video title set VTS 72 in FIG. 8. Videotitle set VTS consists of a plurality of files 74B as in video managerVMG shown in FIG. 14. Each file 74B contains video title set information(VTSI) 94, object set (VTSM_VOBS) for video title set menus, videoobject sets (VTSTT_VOBS; nine files in maximum) for video title settitles, and backup information (VTSI_BUP) for video title setinformation.

As shown in FIG. 16, video title set information VTSI 94 set at thebeginning of video title set VTS 72 describes a video title setinformation management table (VTSI_MAT; mandatory), a title searchpointer table (VTS_PTT_SRPT; mandatory) for a video title setpart_of_title (e.g., chapter of a program), a video title set programchain information table (VTS_PGCIT; mandatory), a video title set menuprogram chain information unit table (VTSM_PGCI_UT; mandatory whenVTSM_VOBS exists), a video title set time map table (VTS_TMAPT; option),a video title set menu cell address table (VTSM_C_ADT; mandatory whenVTSM_VOBS exists), a video title set menu video object unit address map(VTSM_VOBU_ADMAP; mandatory when VTSM_VOBS exists), a video title setcell address table (VTS_C_ADT; mandatory), and a video title set videoobject unit address map (VTS_VOBU_ADMAP; mandatory) in this order.

FIG. 17 shows the contents of video title set information managementtable VTSI_MAT shown in FIG. 16.

As shown in FIG. 17, this video title set information management tableVTSI_MAT describes a video title set identifier (VTS_ID), the endaddress (VT_EA) of the video title set, a played back flag (PLAY_ENDFlag) indicating whether or not a program (e.g., VTS#1 in FIG. 8)recorded on optical disc 10 has been completely played back at leastonce, an archive flag (ARCHIVE Flag) which serves to prevent eraseerrors when a program (e.g., VTS#2 in FIG. 8) recorded on optical disc10 is to be kept without being erased, the end address (VTSI_EA) ofvideo title set information, a version number (VERN) of the format thatthis optical disc (DVD disc) 10 uses, a video title set category(VTS_CAT), the end address (VTSI_MAT_EA) of the video title setinformation management table, the start address (VTSM_VOBS_SA) of thevideo title set menu video object set, the start address (VTSTT_VOBS_SA)of the video title set title video object set, the start address of(VTS_PTT_SRPT_SA) of the video title set part_of_title search pointertable, the start address (VTS_PGCIT_SA) of the video title set programchain information table, the start address (VTSM_PGCI_UT_SA) of thevideo title set menu program chain information unit table, the startaddress (VTS_TMAPT_SA) of the video title set time map table, the startaddress (VTSM_C_ADT_SA) of the video title set menu cell address table,the start address (VTSM_VOBU_ADMAP_SA) of the video title set menu videoobject unit address map, the start address (VTS_C_ADT_SA) of the videotitle set cell address table, the start address (VTS_VOBU_ADMAP_SA) ofthe video title set video object unit address map, information ofattributes of video data, audio data, sub-picture data, and the like,the number of sub-picture streams (VTS_SPST_Ns) of the video title set,a sub-picture stream attribute table (VTS_SPST_ATRT) of the video titleset, and a multichannel audio stream attribute table (VTS_MU_AST_ATRT)of the video title set.

Note that the respective information items of table VTSM_MAT are alignedto the logical block boundaries of data recorded on optical disc 10.

The contents of video title set program chain information tableVTS_PGCIT shown in FIG. 16 will be described.

As shown in FIG. 16, this video title set program chain informationtable VTS_PGCIT contains video title set program chain information tableinformation (VTS_PGCITI), video title set program chain informationsearch pointers (VTS_PGCI_SRP#1 to VTS_PGCI_SRP#n), and video title setprogram chain information (VTS_PGCI).

Note that the order of a plurality of pieces of video title set programchain information VTS_PGCI is set independently of that of the pluralityof video title set program chain information search pointersVTS_PGCI_SRP#1 to VTS_PGCI_SRP#n. Hence, for example, single programchain information VTS_PGCI can be indicated by one or more program chaininformation search pointers VTS_PGCI_SRP.

The contents of video title set program chain information VTS_PGCI shownin FIG. 16 will be described. That is, program chain information (PGCI)is made up of program chain general information (PGC_GI; mandatory), aprogram chain command table (PGC_GI; mandatory), program chain generalinformation (PGC_CMDT; option), a program chain program map (PGC_CMAP;mandatory when C_PBIT to be described below exists), a cell playbackinformation table (C_PBIT; option), and a cell position informationtable (C_POSIT; mandatory when C_PBIT above exists).

The contents of cell playback information table C_PBIT will bedescribed. Cell playback information C_PBIT contains a maximum of 255pieces of cell playback information (C_PBI#1 to C_PBI#n).

The contents of cell playback information C_PBI (C_PBI#1 to C_PBI#n)will be described. Each cell playback information (C_PBI) includes acell category (C_CAT; 4 bytes), cell playback time (C_PBTM; 4 bytes),the start address (C_FVOBU_SA; 4 bytes) of the first video object unit(VOBU) in the cell, the end address (C_FILVU_EA; 4 bytes) of the firstinterleaved unit (ILVU) in the cell, the start address (C_LVOBU_SA; 4bytes) of the last video object unit (VOBU) in the cell, and the endaddress (C_LVOBU_EA; 4 bytes) of the last video object unit (VOBU) inthe cell.

Especially, in this C_PBI, a 1 byte field for setting an eraseprohibition flag is assured at a relative byte position (RBP). When “0”is described in this erase prohibition flag field, data can be freelyerased; when “1” is described, data is to be permanently kept. Thisdescription can be freely made by the user.

The contents of the aforementioned cell category C_CAT will bedescribed. The cell category (C_CAT) indicates the number of cellcommands by the lower 8 bits (b0 to b7); the cell still time by the next8 bits (b8 to b15); the cell type (e.g., karaoke) by the next 5 bits(b16 to b20); an access restriction flag by the next 1 bit (b21); thecell playback mode (e.g., movie still) by the next 1 bit (b22); aseamless angle change flag by 1 bit (b24) after the next reserved bit; asystem time clock (STC) discontinuity flag (to reset STC or not) by thenext 1 bit (b25); an interleaved allocation flag (indicating if the celldesignated by C_PBI is located in a continuous block or an interleavedblock) by the next 1 bit (b26); a seamless playback flag (indicating ifthe cell designated by C_PBI is to be played back seamlessly) by thenext 1 bit (b27); the cell block type (e.g., angle block) by the nexttwo bits (b28 and b29); and the cell block mode (e.g., first cell in theblock) by the last two bits (b30 and b31).

If the cell block mode bits are 00b (b means binary), this means thatthe cell is not the one in the block; if the bits are 01b, the cell isthe first one in the block; if the bits are 10b, the cell is the one inthe block; and if the bits are 11b, the cell is the last one in theblock.

If the cell block type bits are 00b, this indicates that the cell blockdoes not belong to the corresponding block; and if the bits are 01b, thecorresponding block is an angle block (a block containing multianglecells).

If the cell block type bits are not 01b during playback of a titlecontaining multiangle cells, for example, an angle mark (not shown) iskept ON.

On the other hand, if this cell block type=01b is detected duringplayback, the DVD video recorder can inform the viewer that playback ofthe angle block is currently in progress by flickering the angle mark(not shown; or by changing the ON color or shape of the angle mark).With such information, the viewer can make sure that an image in anotherangle pertaining to the picture which is currently being played back isavailable.

If the interleaved allocation flag is 0b, it indicates that thecorresponding cell belongs to a continuous block (that continuouslyrecords a plurality of VOBUs); if the interleaved allocation flag is 1b,the corresponding cell belongs to an interleaved block (thatinterleaved-records ILVUs each containing one or more VOBUs).

If the seamless angle change flag is set (=1b), it represents that thecorresponding cell is to be seamlessly played back; if this flag is notset (=0b), the corresponding cell is to be non-seamlessly played back.

That is, if the interleaved allocation flag=1b and seamless angle changeflag=0b, the angle can be changed non-seamlessly; if the interleavedallocation flag=1b and seamless angle change flag=1b, the angle can bechanged seamlessly.

If a media drive system with a very short access time (a system that canaccess the beginning of a desired angle block within one video frameperiod; not limited to an optical disc drive system) is used, the anglecan be changed smoothly even when the interleaved allocation flag=0b,i.e., between VOBU sets (different angle cells) which are notinterleaved-recorded.

When optical disc 10 with relatively low access speed is used as arecording medium, one recording track of that disc is preferablyassigned to recording of one interleaved block. In such format, sincethe trace destination of an optical head need only move in the radialdirection of the disc by a very small distance corresponding to onetrack width, track jump suffering less time lag (suitable for seamlessangle change) can be attained. In this case, if track jump for one videoobject unit (VOBU) is made, a time lag for a maximum of one revolutionof the disc may be produced. Hence, the angle change that requires jumpsin units of VOBUs is suitable for non-seamless angle change.

Note that the contents of the seamless angle change flag are normallydetermined in advance by the provider (the software producer whoproduces the program contents of titles recorded on DVD disc 10). Thatis, by determining the contents of the seamless angle change flag inadvance, the provider can uniquely whether the non-seamless angle changeor seamless angle change is to be used.

However, it is technically possible to design the DVD video recorderwhich allows the viewer (the user of the DVD video recorder to bedescribed later) to arbitrarily change the contents of the seamlessangle change flag in read data after cell data of the correspondingtitle set are read from the optical disc.

Since the seamless angle change flag represents whether the angleinformation described in navigation pack 86 indicates seamless ornon-seamless angle information, if the user has changed this flag, he orshe should modify angle information (not shown) in navigation pack 86(e.g., modification from seamless angle information to non-seamlessangle information). In this case, the arrangement of packs constitutingthe angle should also be modified, accordingly.

When the cell playback mode is 0b, it indicates continuous playback inthe cell; if the mode is 1b, still playback in each VOBU present in thecell.

When the user makes recording, playback, and the like, the accessrestriction flag can be used upon prohibiting direct selection by useroperation. For example, when the access restriction flag of a cell thatrecords answers for a collection of questions, the user is prohibitedfrom reading the answers by stealth.

The cell type can indicate the following ones by its 5 bit contents, forexample, when the corresponding cell is formed for karaoke.

If the 5 bits are 00000b, no cell type is designated; if the 5 bits are00001b, a title image of the karaoke is designated; if the 5 bits are00010b, an introduction part of the karaoke is designated; if the 5 bitsare 00011b, a song part other than a climax (bridge) part is designated;if the 5 bits are 001000b, a song part of the first climax part isdesignated; if the 5 bits are 00101b, a song part of the second climaxpart is designated; if the 5 bits are 00110b, a song part for a malevocal is designated; if the 5 bits are 01111b, a song part for a femalevocal is designated; if the 5 bits are 01000b, a song part for mixedvoices is designated; if the 5 bits are 01001b, an interlude part(instrumental part) is designated; if the 5 bits are 01010b, fading-inof the interlude part is designated; if the 5 bits are 01011b,fading-out of the interlude part is designated; if the 5 bits are01100b, the first ending part is designated; and if the 5 bits are01101b, the second ending part is designated. The contents of theremaining 5 bit code can be used for other purposes.

Note that the angle change can be applied to that for background videodata of karaoke. (For example, a full-figure shot, closeup shots of theface and mouth, and the like of a singer who is singing a guide vocalcan be angle-changed seamlessly along with the flow of a karaoke musicor non-seamlessly by going back some bars, or during repeat playbackbetween desired bars, as the viewer desired.)

On the other hand, if the 8 bit contents of the cell still time are00000000b, zero still time is designated; if the contents are 11111111b,limitless still time is designated; if the contents fall within therange from 00000001b to 11111110b, a still display time having aduration defined by the decimal value (1 to 254) designated by thecontents and expressed in seconds is designated.

The number of cell commands indicates the number of commands to beexecuted upon completion of playback of the corresponding cell.

FIG. 18 shows the contents of program chain general information PGC_GI.

As shown in FIG. 18, program chain general information PGC_GI describesprogram chain contents (PGC_CNT), a program chain playback time(PGC_PB_TM), program chain user operation control information(PGC_UOP_CTL), a program chain audio stream control table(PGC_AST_CTLT), a program chain sub-picture stream control table(PGC_SPST_CTLT), program chain navigation control information(PGC_NV_CTL), a program chain sub-picture palette (PGC_SP_PLT), thestart address (PGC_CMDT_SA) of a program chain command table, the startaddress (PGC_PGMAP_SA) of a program chain program map, the start address(C_PBIT_SA) of a playback information table of cells in the programchain, and the start address (C_POSIT_SA) of a position informationtable of cells in the program chain.

Program chain contents PGC_CNT indicate the number of programs andnumber of cells (a maximum of 255) in the program chain. In a programchain having no video object VOB, the number of programs is “0”.

The program chain playback time (PGC_PB_TM) represents the totalplayback time of programs in that program chain in hours, minutes,seconds, and the number of video frames. This PGC_PB_TM also describes aflag (tc_flag) indicating the type of video frame, and a frame rate (25or 30 frames per sec) or the like is designated by the contents of thisflag.

Program chain user operation control information PGC_UOP_CTL indicatesuser operations prohibited in the program chain which is being playedback.

Program chain audio stream control table PGC_AST_CTLT can containcontrol information for each of eight audio streams. Each controlinformation includes a flag (availability flag) indicating if thecorresponding audio stream is available in that program chain, andconversion information from an audio stream number to an audio streamnumber to be decoded.

Program chain sub-picture stream control table PGC_SPST_CTLT includes aflag (availability flag) indicating if that sub-picture stream isavailable in the corresponding program chain, and conversion informationfrom a sub-picture stream number (32 numbers) into the sub-picturestream number to be decoded.

Program chain navigation control information PGC_NV_CTL includesNext-PGCN indicating the next program chain number to be played backafter the program chain which is currently being played back,Previous_PGCN indicating a program chain number (PGCN) quoted by anavigation command “LinkPrevPGC” or “PrevPGC_Search( )”, GoUp_PGCNindicating a program chain number to which that program chain is toreturn, a PG Playback mode indicating the playback mode (sequentialplayback, random playback, shuffle playback, and the like) of theprogram, and a Still time value indicating the still time after thatprogram chain is played back.

Program chain sub-picture palette PGC_SP_PLT describes 16 sets ofluminance signals and two color difference signals used in a sub-picturestream in that program chain.

Start address PGC_CMDT_SA of the program chain command table assures adescription area for a pre-command executed before PGC playback, apost-command executed after PGC playback, and a cell command executedafter cell playback.

Start address PGC_PGMAP_SA of the program chain program map describesthe start address of program map PGC_PGMAP representing the programconfiguration in the program chain by a relative address from the firstbyte of program chain information PGCI.

Start address C_PBIT_SA of the cell playback information table in theprogram chain describes the start address of cell playback informationtable C_PBIT that determines the playback order of cells in that programchain by a relative address from the first byte of program chaininformation PGCI.

Start address C_POSIT_SA of the position information table of cells inthe program chain describes the start address of cell positioninformation table C_POSIT indicating VOB identification numbers and cellidentification numbers used in that program chain by a relative addressfrom the first byte of program chain information PGCI.

FIG. 19 shows an example of the arrangement of an apparatus (DVD videorecorder) for recording and playing back digital moving pictureinformation on and from a disc shown in FIG. 1 at a variable recordingrate using information with the structure described above with referenceto FIGS. 3 to 18.

The apparatus main body of the DVD video recorder shown in FIG. 19 isroughly constructed by a disc drive unit (32, 34, and the like) forrotating DVD-RAM or DVD-R disc 10, and reading/writing informationto/from disc 10, encoder 50 on the recording side, decoder 60 on theplayback side, and microcomputer block 30 for controlling operations ofthe apparatus main body.

Encoder 50 comprises ADC (analog-to-digital converter) 52, video encoder(V encoder) 53, audio encoder (A encoder) 54, sub-picture encoder (SPencoder) 55, formatter 56, and buffer memory 57.

ADC 52 receives an external analog video signal+external analog audiosignal from AV input 42, or an analog TV signal+analog audio signal fromTV tuner 44. ADC 52 converts the input analog video signal into adigital signal at sampling frequencies of, e.g., 13.5 MHz/6.75M and 8quantization bits. (That is, luminance component Y at a samplingfrequency of 13.5M, color difference component Cr (or Y-R) at a samplingfrequency of 6.75M, and color difference component Cb (or Y-B) at asampling frequency of 6.75M are respectively quantized, with the ratioof 4:2:2, by 8 bits). Incidentally, all components Y, Cr and Cb may besampled with 13.5M, so that they are quantized, in the ratio of 4:4:4,by 8 bits.

Similarly, ADC 52 converts the input analog audio signal into a digitalsignal at a sampling frequency of, e.g., 48 kHz and 16 quantizationbits.

When an analog video signal and digital audio signal are input to ADC52, the digital audio signal passes through ADC 52. (The digital audiosignal may be subjected to processing for reducing jitter alone,processing for changing the sampling rate or the number of quantizationbits, and the like without changing its contents.)

On the other hand, when a digital video signal and digital audio signalare input to ADC 52, these signals pass through ADC 52 (these signalsmay also be subjected to jitter reduction, sampling rate changeprocessing, and the like without changing their contents).

A digital video signal component output from ADC 52 is supplied toformatter 56 via video encoder (V encoder) 53. Also, a digital audiosignal component output from ADC 52 is supplied to formatter 56 viaaudio encoder (A encoder) 54.

V encoder 53 has a function of converting the input digital video signalinto a digital signal compressed at a variable bit rate by MPEG2 orMPEG1.

A encoder 54 has a function of converting the input digital audio signalinto a digital signal compressed at a fixed bit rate (or linear PCMdigital signal) by MPEG or AC-3.

When a DVD video signal with the data structure shown in FIGS. 11 and 12is input from AV input 42 (e.g., a signal coming from a DVD video playerwith a dedicated sub-picture signal output terminal), or when a DVDvideo signal with such data structure is broadcasted and received by TVtuner 44, a sub-picture signal component (sub-picture pack) in the DVDvideo signal is input to sub-picture encoder (SP encoder) 55.Sub-picture data input to SP encoder 55 is arranged into a predeterminedsignal format, and is then supplied to formatter 56.

Formatter 56 performs predetermined signal processing for the inputvideo signal, audio signal, sub-picture signal, and the like while usingbuffer memory 57 as a work area, and outputs recording data that matchesthe format (file structure) described above with reference to FIGS. 3 to18 to data processor 36.

The contents of standard encoding for generating the recording data willbe briefly explained. That is, when encoder 50 shown in FIG. 19 startsencoding, parameters required for encoding video (main picture) data andaudio data are set. The main picture data is pre-encoded using the setparameters to calculate an optimal code amount distribution for apredetermined average transfer rate (recording rate). Based on the codeamount distribution obtained by pre-encoding, the main picture data isencoded. At this time, the audio data is encoded at the same time.

As a result of pre-encoding, when data compression is insufficient (whena desired video program cannot be stored in a DVD-RAM or DVD-R disc usedto record data), if pre-encoding can be done again (for example, if therecording source is the one capable of repetitive playback such as avideo tape, video disc, or the like), the main picture data is partiallyre-encoded, and the re-encoded main picture data portion replaces thepreviously pre-encoded main picture data portion. With a series of suchprocesses, the main picture data and audio data are encoded, and theaverage bit rate value required for recording is reduced largely.

Likewise, parameters required for encoding the sub-picture data are set,and encoded sub-picture data is generated.

The encoded main picture data, audio data, and sub-picture data arecombined and converted into the structure of video title set VTS.

That is, cells as minimum units of the main picture data (video data)are set, and the cell playback information (C_PBI) is generated. Then,the structure of cells that construct a program chain shown in FIG. 8,attributes of main picture, sub-picture, and audio data, and the likeare set (some of these attributes use information obtained upon encodingthe individual data), and information management table information(VMGI_MAT in FIG. 15 and VTSI_MAT in FIG. 16) containing various kindsof information is created.

The encoded main picture data, audio data, and sub-picture data aresegmented into packs each having a predetermined size (2,048 bytes)shown in FIG. 12, and dummy packs are appropriately inserted into thesepacks. Packs other than the dummy packs describe time stamps such as aPTS (presentation time stamp), DTS (decode time stamp), and the like. Asfor the PTS of sub-picture data., a time arbitrarily delayed from thatof main picture data or audio data in the same playback time zone can bedescribed.

The data cells are arranged while adding navigation pack 86 at thebeginning of each VOBU 85 so as to play back data in the order fromtheir time codes, thus forming VOB 83 constructed by a plurality ofcells, as shown in FIG. 11. VOBS 82 containing one or more VOBs 83 isformatted to the structure of VTS 72 shown in FIG. 8.

When a DVD playback signal is digitally copied from a DVD video player,since the contents of cells, program chain, management tables, timestamps, and the like are predetermined, they need not be generatedagain. (When a DVD video recorder is designed to digitally copy a DVDplayback signal, copyright protection means such as an electronicwatermark, and the like must be taken.)

The disc drive unit that writes/reads (records/plays back) informationto/from DVD disc 10 comprises disc changer 100, disc drive 32, temporalstorage 34, data processor 36, and system time counter (or system timeclock; STC) 38.

Temporal storage 34 is used for buffering a predetermined amount ofthose of data to be written in disc 10 via disc drive 32 (i.e., dataoutput from encoder 50), and for buffering a predetermined amount ofthose of data played back from disc 10 via disc drive 32 (i.e., datainput to decoder 60).

For example, when temporal storage 34 is comprised of a 4 Mbytesemiconductor memory (DRAM), it can buffer recording or playback datafor approximately 8 sec at an average recording rate of 4 Mbps. On theother hand, when temporal storage 34 is comprised of a 16 Mbyte EEPROM(flash memory), it can buffer recording or playback data forapproximately 30 sec at an average recording rate of 4 Mbps.Furthermore, when temporal storage 34 is comprised of a 100 Mbyte verycompact HDD (hard disc), it can buffer recording or playback data for 3min or more at an average recording rate of 4 Mbps.

Temporal storage 34 can also be used for temporarily storing recordinginformation until disc 10 is exchanged by a new one, when disc 10 hasbeen fully recorded during recording.

Temporal storage 34 can be used for temporarily storing data excessivelyread out from the drive within a predetermined period of time when discdrive 32 uses a high-speed drive (double-speed or higher). When readdata upon playback is buffered on temporal storage 34, even when anoptical pickup (not shown) has produced read errors due to a vibrationshock or the like, playback data buffered on temporal storage 34 can beused alternatively, thus preventing a played back picture from beinginterrupted.

When the DVD video recorder has an external card slot (not shown in FIG.19), the EEPROM may be sold as an optical IC card. On the other hand,when the DVD video recorder has an external drive slot or SCSIinterface, the HDD can be sold as an optical expansion drive.

Data processor 36 in FIG. 19 supplies DVD recording data output fromencoder 50 to disc drive 32, receives a DVD playback signal played backfrom disc 10 via drive 32, rewrites management information (thedirectory records described subsequent to FIG. 10, VMGI_MAT in FIG. 15,VTSI_MAT in FIG. 16, and the like) recorded in disc 10, and erases data(files or VTS) recorded on disc 10 under the control of microcomputerblock 30.

Microcomputer block 30 includes an MPU (or CPU), ROM written withcontrol programs and the like, and a RAM that provides a work arearequired for executing programs.

The MPU in microcomputer block 30 (to be also referred to as MPU 30hereinafter) executes free space detection, recording amount (the numberof recorded packs) detection, remaining amount detection, warning,recording mode change instruction, and other processes using the RAM asa work area in accordance with the control programs stored in the ROM.

Of the execution results of MPU 30, the contents that the DVD videorecorder user is informed of are displayed on display 48 of the DVDvideo recorder, or are displayed on a monitor display in an on-screendisplay (OSD) mode.

The control timings of disc changer 100, disc drive 32, data processor36, and encoder 50 and/or decoder 60 by MPU 30 can be determined basedon time data output from STC 38 (recording and playback are normallydone in synchronism with time clocks from STC 38, but other processesmay be executed at timings independently of STC 38).

Decoder 60 comprises separator 62 for separating and extracting packsfrom DVD playback data with the pack structure shown in FIG. 11, memory63 used upon signal processes such as pack separation and the like,video decoder (V decoder) 64 for decoding main picture data (thecontents of video pack 88 in FIG. 11) separated by separator 62,sub-picture data decoder (SP decoder) 65 for decoding sub-picture data(the contents of sub-picture pack 90 shown in FIG. 11) separated byseparator 62, audio decoder (A decoder) 68 for decoding audio data (thecontents of audio pack 91 in FIG. 11) separated by separator 62, videoprocessor 66 for appropriately synthesizing sub-picture data output fromSP decoder 65 with video data output from V decoder 64, and outputtingmain picture data with superimposed sub-picture data such as menus,highlight buttons, superimposed dialog, and the like, videodigital-to-analog converter (V•DAC) 67 for converting a digital videooutput from video processor 66 into an analog video signal, and audiodigital-to-analog converter (A•DAC) 67 for converting a digital audiooutput from A decoder 68 into an analog audio signal.

The analog video signal output from V•DAC 67 and analog audio signalfrom A•DAC 69 are supplied to output device 46 a (not shown; amultichannel stereophonic apparatus having two to six channels+monitorTV or projector) via AV output 46.

OSD data output from MPU 30 is input to separator 62 of decoder 60, andis then input to video processor 66 through V decoder 64 (without beingdecoded). The OSD data is superimposed on main picture data, and thesedata are supplied to an external monitor TV connected to AV output 46.Then, a warning message is displayed together with a main picture.

MPU 30 is connected to printer interface P1. Printer interface P1 isconnected to printer P2. Printer P2 prints out images based on variousdata played back from optical disc 10 to predetermined locations (anoptical disc, a label added to an optical disc, a cartridge which storesan optical disc, and the like).

When the user has pressed open/close button 5 g of remote controller (tobe described later with reference to FIG. 20), a disc tray (not shown)is opened toward the user side.

DVD-RAM or DVD-RW disc (a cartridge containing a disc) 10 or DVD-R disc(bear disc) 10 used in recording is set on this disc tray.

Subsequently, when the user has pressed open/close button 5 g on remotecontroller 5, disc tray door 202 is closed, and disc (e.g., DVD-RW) seton the tray is loaded into disc drive 32 in apparatus main body 200.

Then, disc drive 32 is automatically started, and MPU 30 reads physicalformat information (including disc structure data, free space data of ablank disc, and the like). After that, MPU 30 reads a video managerinformation management table (including information FREE_SPACEindicating a practical free space, and the like) shown in FIG. 15, and avideo title set information management table (including PLAY_END Flagindicating whether or not a specific title set has already been playedback, ARCHIVE Flag indicating whether or not a specific title set is tobe permanently kept, and the like) shown in FIG. 17.

When set disc 10 is a new DVD-RW disc (or DVD-RAM disc), an item“DVD-RW” (or “DVD-RAM”) on display 48 of the DVD video recorder is beingprominented in an easy-to-see manner. Also, a recording time “00(hour):00 (min):00 (sec)” is displayed, and a recording title/chapter“00-00” is displayed (once recording has been done, the recordingtitle/chapter display changes like “01-01”).

If the apparatus default or user setup indicates a recording mode=MPEG2and a recording average bit rate=4 Mbps, items “MPEG2” and “4 Mbps” aredisplayed on display 48 to stand out.

Furthermore, when recording on set disc 10 has progressed, and therecordable time on that disc 10 becomes small (e.g., 5 min), MPU 30detects it, and an item “DISK TO BE CHANGED” that prompts the user toexchange the disc is displayed on display 48 in an easy-to-see manner.

The front panel of DVD video recorder main body 200 also has basicoperation keys such as a power switch button, open/close key, playbackkey, stop key, chapter/program skip key, rewind key, fastforward key,recording start button (not shown), and the like.

The above-mentioned item “DISK TO BE CHANGED” begins to be lit up orflicker slightly before disc 10 set in the apparatus main body is usedup during recording. After that when the remaining amount of disc 10becomes zero, recording automatically proceeds to one or more DVD-RWdisc 10 set in external disc changer 100.

Alternatively, two or more DVD video recorders may be prepared, andtheir MPUs 30 may be connected by daisy chain via a communication cableto attain relay recording using two or more DVD video recorders. In suchcase, it is possible that “the first recorder can record usingMPEG2/average bit rate=4 Mbps for 1 hour, and the second recorder canrecord using MPEG2/average bit rate=2 Mbps for 2 hours”.

In case of relay recording using a plurality of DVD video recorders, amessage “recorder A records using MPEG2/average bit rate=4 Mbps for 1hour, and recorder B records using MPEG2/average bit rate=2 Mbps for 2hours” may be displayed on the monitor screen.

Note that the DVD video recorder shown in FIG. 19 does not record anywarning or messages to the user on disc 10. However, recordinginformation (recording average bit rate, recording channel number,recording date/time, and the like) exemplified on the lower portion ofthe monitor screen may be recorded on disc 10 for several secondsimmediately after the beginning of recording.

FIG. 20 shows an example of remote controller 5 used for operating theDVD video recorder shown in FIG. 19. Remote controller 5 shown in FIG.20 has various keys such as power key 5 a, open/close key 5 g, menu key5 n, select/cursor key 5 q, display key 5 u, and print key 5pri.

Power key 5 a is literally used to turn on/off the power supply.Open/close key 5 g is used to open/close disc tray 202 (not shown)mounted on apparatus main body 200 of the DVD video recording shown inFIG. 19. Menu key 5 n is used to play back/display root menus recordedon a disc and selected menus. Select/cursor key 5 q is used to selectvarious items. Display key 5 u is used to display various pieces ofinformation on display 48. The function of print key 5pri will beexplained in detail below.

A representative frame will be described.

Video object DA22 of optical disc 10 includes moving picture dataconstructing a plurality of chapters (first, second, . . . , nthchapters). This moving picture data includes a plurality of picture datacorresponding to a plurality of frames. The plurality of frames includerepresentative frames each representing a corresponding chapter. Therepresentative frame is a frame to be reduced for the following reason.The representative frame is also a frame to be printed. Picture datacorresponding to this representative frame is the above-describedrepresentative picture data. That is, information indicating the storagelocation of the representative picture data is start address data INFO11and length data INFO12.

The relationship between a main frame and subframe will be explained.

Moving picture data included in video object DA22 of optical disc 10 isdata compressed by a compression format determined by MPEG2. This movingpicture data includes base picture data corresponding to a base picture(I picture: Intra-Picture), and change data indicating a change (motion)in base picture. The base picture data included in the moving picturedata forms a main frame, and the change data forms a subframe. Thesubframe is a picture subsequent to the main frame. That is, mainpicture data (base picture data) corresponding to the main frame, andsub-picture data corresponding to the subframe are played back in thisorder. In this embodiment, for example, the representative framecorresponds to the main frame. In other words, information indicatingthe storage location of main picture data corresponding to the mainframe is start address data INFO11 and length data INFO12.

The skip playback function will be explained.

The digital information recording/playback system has a function (skipplayback function) of playing back moving picture data from apredetermined position (predetermined chapter). To realize this skipplayback function, picture object DA23 of optical disc 10 records menuframe information for creating a skip playback menu frame. When thedigital information recording/playback system receives a menu displayinstruction via menu key 5 n of remote controller 5, it reads menu frameinformation from optical disc 10 and displays a skip playback menu frameon output device (monitor or the like) 46 a based on this menu frameinformation.

The skip playback menu frame includes the first representative framerepresenting the first chapter, the second representative framerepresenting the second chapter, . . . , and the nth representativeframe representing the nth chapter. In displaying the skip playback menuframe, the digital information recording/playback system reads startaddress data INFO11 and length data INFO12 and reads out representativepicture data from the storage location of the representative picturedata. This representative picture data is reduced to display arepresentative frame of each chapter on the skip playback menu frame. Atthis time, if the digital information recording/playback system receivesdesignation of a predetermined representative frame via selectkey/cursor key 5 q of remote controller 5, it starts playing back movingpicture data from a chapter corresponding to the predeterminedrepresentative frame. In this way, the skip playback function isrealized.

Printing of information about the recording contents of optical disc 10will be described.

According to the present invention, information about the recordingcontents of optical disc 10 is printed on the surface of optical disc10, a cartridge which stores optical disc 10, or a label added tooptical disc 10. This allows the user to obtain information about therecording contents of optical disc 10 without playing back optical disc10. Information about the recording contents of optical disc 10corresponds to representative picture data equivalent to arepresentative frame (a frame to be printed or main frame). Informationabout the recording contents of optical disc 10 also includes pictureinformation INFO7 (recording date information INFC71, recording channelinformation INFO72, white balance information INFO73, zoom ratioinformation INFO74, shutter speed information INFO75, and GPSinformation INFO76). Further, information about the recording contentsof optical disc 10 also includes amount information 271 (total amountinformation 2711 and free area information 2712), and rewrite countinformation 701.

Printing of information about the recording contents of optical disc 10will be explained with reference to a flow chart in FIG. 21.

The digital information recording/playback system has a function(recording-related matter printing function) of printing informationabout the recording contents of optical disc 10. To realize thisrecording-related matter printing function, volume/file managementinformation 70 of optical disc 10 records menu frame information forcreating a print menu frame. When the digital informationrecording/playback system receives a recording-related matter printinstruction via print key 5pri of remote controller 5 (YES in ST1), itreads menu frame information from optical disc 10 and displays a printmenu frame on output device 46 a based on this menu frame information(ST2).

Print targets are displayed on the print menu frame. That is,representative frames (first, second, . . . , nth representativeframes), picture information INFO7 (recording date information INFO71,recording channel information INF072, white balance information INFO73,zoom ratio information INFO74, shutter speed information INF075, and GPSinformation INFO76), amount information 271 (total amount information2711 and free area information 2712), rewrite count information 701, andthe like are displayed on the print menu frame. In displaying the printmenu frame, the digital information recording/playback system readsstart address data INFO11 and length data INFO12 and reads outrepresentative picture data form the storage location of therepresentative picture data. This representative picture data is reducedto display a representative frame of each chapter on the print menuframe. In displaying the print menu frame, the digital informationrecording/playback system reads picture information INFO7 (recordingdate information INFO71, recording channel information INF072, whitebalance information INFO73, zoom ratio information INFO74, shutter speedinformation INF075, and GPS information INFO76), amount information 271(total amount information 2711 and free area information 2712), andrewrite count information 701. The digital informationrecording/playback system displays the read information on the printmenu frame.

If the digital information recording/playback system receivesdesignation of a print target via the operation panel after the printmenu frame is displayed on output device 46 a (YES in ST3), it instructsthe printer to print the designated print target. The printer executesimage formation based on data of the designated print target inaccordance with this instruction. That is, the printer prints thedesignated print target to a predetermined print destination (ST4). Theprint destination at this time is the surface of optical disc 10, acartridge which stores optical disc 10, a label added to optical disc10, or the like.

FIG. 22 is a view showing the state in which picture information INFO7(recording date information INFO71, recording channel informationINF072, white balance information INFO73, zoom ratio information INFO74,shutter speed information INF075, and GPS information INFO76) is printedon a label added to optical disc 10 and cartridge 11.

FIGS. 23A, 23B, and 23C are views showing the state in which amountinformation 271 (total amount information 2711 and free area information2712) is printed on a label added to cartridge 11. FIG. 23A is a viewshowing the state in which amount information 271 (free area) isnumerically represented. FIG. 23B is a view showing the state in whichamount information 271 (remaining recording time) is numericallyrepresented. The recording time changes in accordance with thecompression ratio of image data recorded on optical disc 10, so anaccurate remaining recording time cannot be obtained from a free area.In this case, an approximate remaining recording time is printed. FIG.23C is a view showing the state in which amount information 271 (freearea) is illustrated. By representing used and unused amounts incontrast with each other, as shown in FIG. 23C, the user can visuallycheck the storage amount.

FIGS. 24A and 24B are views showing the state in which rewrite countinformation 701 is printed on a label added to optical disc 10. Data isassumed to be frequently rewritten on an optical disc such as DVD-RAM.However, the number of rewrite operations is limited, and if the rewritecount exceeds a given count, a write disable area is generated. Thewrite disable area is replaced, but too many write disable areas resultin a short of the data recording time owing to replacement and datarecording errors. To make the user know this in advance, the rewritecount is printed. FIG. 24A is a view showing the state in which rewritecount information 701 is numerically represented. FIG. 24B is a viewshowing the state in which rewrite count information 701 is illustrated.

According to the present invention, an information recording mediumprocessing apparatus which can easily display information about therecording contents of an information recording medium without anyplayback and cumbersome processing of the information recording medium(optical disc) can be provided.

According to the present invention, an information recording mediumwhich can contribute to easy display of information about the recordingcontents of the information recording medium without any playback andcumbersome processing of the information recording medium (DVD-RAMdisc).

A modification of the embodiment mentioned above will be described withreference to FIGS. 25 to 31. In the above embodiment, start address dataINFO11 and length data INFO12 shown in FIG. 7 indicate the storagelocation of a representative picture included in video object DA22 shownin FIG. 3. However, the present invention is not limited to this, andthe storage location of the representative picture may be indicated asfollows.

<1> General Description of Data Structure of Information RecordingMedium (Optical Disk 1001)

Data (video data, audio data, and the like) recorded on optical disc1001 shown in the uppermost stage in FIG. 25 has a structure shown inthe second stage in FIG. 25 from inner side 1006 to outer side 1007. Thedata structure shown in the second stage in FIG. 25 has details shown inthe third, fourth, fifth, and sixth stages in FIG. 25.

More specifically, as shown in FIG. 25, optical disc 1001 includeslead-in area 1002, volume & file manager information 1003, data area1004, and lead-out area 1005. Lead-in area 1002 includes an embosseddata zone having an uneven optical reflection surface, a mirror zonehaving a flat surface (mirror surface), and a rewritable data zonecapable of information rewrite. Volume & file manager information 1003includes a rewritable data zone capable of recording/rewriting an audio& video data file or information about the total volume by the user.Data area 1004 includes a rewritable data zone capable ofrecording/rewriting data by the user. Lead-out area 1005 includes arewritable data zone capable of information rewrite.

The embossed data zone of lead-in area 1002 records in advanceinformation about the whole disc, information about recording, playback,and erase characteristics, and information about the manufacture of thedisc. Information about the whole disc is information such as the disctype (DVD-ROM, DVD-RAM, DVD-R, or the like), the disc size, therecording density, the physical sector number (PSN) indicating therecording start/end position, and the like. Information about recording,playback, and erase characteristics is information such as the recordingpower, the recording pulse width, the erase power, the playback power,the recording/erase linear velocity, and the like. Information about themanufacture of the disc is information about the manufacture of eachdisc such as the manufacturing number.

The rewritable data zones of lead-in and lead-out areas 1002 and 1005have unique disc name recording areas for respective informationrecording media, test recording areas (for confirming recording/eraseconditions), and management information recording areas about defectiveareas in data area 1004. These areas allow recording by the informationrecording/playback system.

As shown in FIG. 25, data area 1004 sandwiched between lead-in andlead-out areas 1002 and 1005 allows mixed recording of computer data andaudio & video data. The recording order and recording information sizesof computer data and audio & video data can be arbitrarily set. Areaswhich record computer data will be called computer data areas 1008 and1010, and an area which records audio & video data will be called audio& video data area 1009.

As shown in FIG. 25, audio & video data area 1009 includes controlinformation 1011, video objects 1012, picture objects 1013, and audioobjects 1014. Control information 1011 is control information necessaryfor processes such as picture recording (sound recording), playback,editing, and search. Video objects 1012 are contents (recordinginformation) of video data. Picture objects 1013 are still pictureinformation such as still pictures and slide pictures. Audio objects1014 are contents (sound recording information) of audio data.

Video objects 1012, picture objects 1013, and audio objects 1014 shownin FIG. 25 mean information groups classified in units of contents (datacontents). All video data recorded in audio & video data area 1009 areincluded in video objects 1012, all pieces of still picture informationare included in picture objects 1013, and all audio•sound data areincluded in audio objects 1014.

Original cell=VOB (video object) 1403 shown in FIG. 27 represents a setof pieces of information recorded in AV file 1401, and has a definitiondifferent from that of video objects 1012 shown in FIG. 25. These termsare similar but used with different meanings.

As shown in FIG. 25, control information 1011 includes RTRW videomanager information (RTRW_VMGI) 1021, movie AV file information table(M_AVFIT) 1022, still picture AV file information table (S_AVFIT) 1023,original PGC information (ORG_PGCI) 1024, user defined PGC informationtable (ORG_PGCI) 1025, text data manager (TXT_DT_MG) 1026, andmanufactures information table (MNFIT) 1027. RTRW video managerinformation (RTRW_VMGI) 1021 is common to all RTR (Real Time Recording)shown in FIG. 26, and includes information indicating the storagedestination of a representative picture. The representative picture isused as a picture to be printed on a disc label (a picture representingthe recording contents of a disc). Alternatively, when a plurality ofdiscs are handled in an autochanger or multi-disc pack, therepresentative picture is used as a picture representing the recordingcontents of a disc loaded into the disc drive (a picture displayed as apreview on the display). Movie AV file information table (M_AVFIT) 1022and still picture AV file information table (S_AVFIT) 1023 manage datastructures in video object 1012, and information about recordingpositions on optical disc 1001. Original PGC information (ORG_PGCI) 1024and user defined PGC information table (ORG_PGCI) 1025 have controlinformation necessary for playback. Text data manager (TXT_DT_MG) 1026and manufactures information table (MNFIT) 1027 correspond to additionalrecording/playback information.

As shown in FIG. 25, movie AV file information table (M_AVFIT) 1022 andstill picture AV file information table (S_AVFIT) 1023 includeallocation map table 1105, video title set information 1106, and videoobject information 1107. Original PGC information (ORG_PGCI) 1024 anduser defined PGC information table (ORG_PGCI) 1025 include PGC controlinformation 1103 and cell playback information 1108. Allocation maptable 1105 records information about address setting along practicalallocation on optical disc 1001 and identification of recorded andunrecorded areas. Video title set information 1106 represents theoverall information in AV file 1401 shown in FIG. 27, and includes linkinformation between VOBs, grouping information of a plurality of VOBsfor management and search, and time information such as a time maptable. As shown in FIG. 27, video object information 1107 representsinformation about each VOB in AV file 1401, and includes attribute(characteristic) information for each VOB and information about eachvideo object unit (VOBU) contained in the VOB. PGC control information1103 includes information about a video data playback program(sequence). Cell playback information 1108 includes information aboutthe data structure of a basic video data unit for playback.

The structure in FIG. 25 has been schematically explained, and eachinformation will be slightly supplementally explained.

Volume & file manager information 1003 records information about thetotal volume, the number of PC data files, the number of AV data files,and recording layer information.

In particular, as the recording layer information, the followinginformation is recorded to process a multi-disc pack or two-layeredRAM/ROM disc as one large volume space by setting successive logicalsector numbers.

-   -   The number of constituent layers (e.g., one two-layered RAM/ROM        disc is counted as two layers, one two-layered ROM disc is        counted as two layers, and n single-sided discs are counted as n        layers.)    -   A logical sector number range table assigned to each layer (the        amount of each layer)    -   The type of each layer (e.g., a DVD-RAM disc, a RAM portion of a        two-layered RAM/ROM disc, a CD-ROM, a CD-R, or the like)    -   A logical sector number range table assigned in units of zones        in the RAM area of each layer (also including rewritable area        amount information of each layer)    -   ID information unique to each layer (to check disc exchange in a        multi-disc pack)        <2> Directory Structure of Data File in Data Area 1004

All pieces of information recorded in data area 1004 in FIG. 25 arerecorded in units of files, and the relationship between data files ismanaged by a directory structure, as shown in FIG. 26.

FIG. 39 illustrates the directory and files where the data whichcomplies with this Specifications are recorded. All the files associatedwith the Program Set and Play Lists are Placed under DVD_RTR directory.Under the directory, the following files are created.

-   -   RTR.IFO

Navigation data to represent Programs Entry Points, Play Lists, and soon are recorded in this file. This file shall exists as long as anycontents compliant to this Specifications are recorded. The Navigationdata to be recorded in this file are to be described in the followingsections.

-   -   RTR_MOV.VRO

Stream data categorized in Movie VOB are recorded in this file.Therefore as long as any Movie VOB exists, this file shall exist.

Control information 1011 in FIG. 25 is recorded as one file serving asrecording/playback video management data. Control information 1011 inFIG. 25 has a file name “RTR.IFO” in FIG. 26. Video objects 1012 in FIG.25 have a file name “RTR_MOV.VRO” in FIG. 26. Picture objects 1013 inFIG. 25 have a file name “RTR_STO.VRO” in FIG. 26. Audio objects in FIG.25 have a file name “RTR_STA.VRO” in FIG. 26. RTRW_STA.VRO represents anafter-recording file of a still picture (RTRW_STO.VRO). Video objects1012, picture objects 1013, and audio objects 1014 are recorded as oneAV file 1401 shown in FIG. 27.

<3> Data Structure in AV File

FIG. 27 shows a data structure in the AV file. As shown in FIG. 27, AVfile 1401 constitutes program set (original PGC) 1402 as a whole.Program set 1402 consists of a set of a plurality of original cells=VOBs(video objects) 1403, 1404, and 1405 divided in accordance with thecontents of audio & video data and the order of information recorded inAV file 1401.

VOBs 1403, 1404, and 1405 in FIG. 27 are defined as a set of audio &video data recorded in AV file 1401, and have definition contentsdifferent from those of video objects 1012 shown in FIG. 25 thatsubstantially serve as classification items for video data, stillpicture information, audio data, and the like. Therefore, VOBs 1403,1404, and 1405 in FIG. 27 record not only information classified intovideo objects 1012, but also information classified into picture objects1013 and audio objects 1014.

Contents recorded in VOBs 1403, 1404, and 1405 are grouped in units ofrelated VOBs, and respective groups are combined as PGs (programs) 1407and 1408. That is, PGs 1407 and 1408 are constituted as sets of one orplurality of VOBs. In FIG. 27, PG 1408 is constituted by two VOBs 1404and 1405, and PG 1407 is constituted by only one VOB.

The minimum basic units of video data are called VOBU 1411 to 1414, anddata in VOBs 1403 to 1405 are constituted as sets of VOBUs (video objectunits) 1411 to 1414, as shown in FIG. 27. Video data compression usingthe VOB often employs MPEG1 or MPEG2. In MPEG, video data are groupedinto GOPs every 0.5 sec, and compressed in units of GOPs. The video datacompression unit of VOBUs 1411 to 1414 is formed in synchronism with theGOP with almost the same size as that of the GOP.

VOBUs 1411 to 1414 include one or more frames. More specifically, VOBUs1411 to 1414 are divisionally recorded as 2,048 byte sectors 1431 to1437. Each of sectors 1431 to 1437 is recorded with a pack structureformat. In units of packs, raw video data, sub-video data, audio data,and dummy data are recorded in the forms of V_PCKs (Video Packs) 1421,1425, 1426, and 1427, SP_PCK (Sub-picture Pack) 1422, A_PCK (Audio Pack)1423, DM_PCK (Dummy Pack) 1424. Each pack has a 14 byte pack header atits beginning, and thus the information amount recorded in each pack is2,034 bytes.

The recording area of a DVD-RAM disc as an example of optical disc 1001shown in FIG. 25 is divided into a plurality of sectors. One sector canrecord 2,048 byte data. On this DVD-RAM disc, recording/playback isperformed in units of sectors. When the DVD-RAM disc is used as opticaldisc 1001, respective packs are recorded in units of sectors 1431 to1437, as shown in FIG. 27.

As shown in FIG. 27, a series of all VOBs 1403 to 1405 in AV file 1401constitute program set 1402. An arbitrary range in an arbitrary VOB isdesignated and played back in an arbitrary playback order in accordancewith a playback procedure programmed in original PGC information(ORG_PGCI) 1024 and user defined PGC information table (ORG_PGCI) 1025.The basic video data basic unit for playback will be called cells (userdefined cells) 1441, 1442, and 1443. Cells 1441, 1442, and 1443 candesignate an arbitrary range in an arbitrary VOB, but cannot designate arange over VOBs (one cell cannot set a range by linking a plurality ofVOBs).

In FIG. 27, cell 1441 designates one VOBU 1412 in VOB 1403, cell 1442designates one entire VOB 1404, and cell 1443 designates the range ofonly a specific pack (V_PCK 1427) in VOBU 1414.

Information representing the video data playback sequence is set by PGC(user defined program chain) 1446. This playback sequence is designatedby one cell or described by link information between a plurality ofcells. For example, in FIG. 27, PGC 1446 constitutes a playback programas a link between cells 1441, 1442, and 1443.

<4> Contents of Allocation Map Table

As described above, the recording area of the DVD-RAM disc is dividedinto a plurality of sectors, and the sectors are added with logicalsector numbers (LSNs) in an ascending order from the inner side.

Assume that video data is recorded in data area 1004 of optical disc1001 by the following procedure.

(1) A recording area of AV file 1401 is ensured in a continuous area(a<g) from LSNs a+1 to g in data area 1004 on optical disc 1001.

(2) Data of VOB#1 1461 is recorded in a continuous area (b<c) from LSNsb+1 to c in the recording area of AV file 1401.

(3) Data of VOB#2 1462 is recorded in a continuous area (d<e) from LSNsd+1 to e in the recording area of AV file 1401.

As a result of processes (1) to (3), three unrecorded areas from LSN“a+1 to b”, “c+1 to d”, and “e+1 to g” are left in AV file 1401. Videodata of VOB#3 having a large data size is recorded in the unrecordedareas by the following procedure.

(4) Data of VOB#3 is divided into a plurality of segments in accordancewith the unrecorded area size in the recording area of AV file 1401.

(5) The first data of the divided VOB#3 is recorded in a continuous area(a<b) from LSN a+1 to b.

(6) The second data of the divided VOB#3 is recorded in a continuousarea (c<d) from LSN c+1 to d.

(7) The last data of the divided VOB#3 is recorded in a continuous area(f<g) from LSN f+1 to g.

Consequently, unrecorded area 1460 from LSN “e+1 to f” is left in AVfile 1401. FIG. 28 shows the physical recording position distribution ofrespective VOBs in AV file 1401 that is obtained as a result ofprocesses (1) to (7).

As is apparent from the above description, if data in AV file 1401 ispartially erased, or new data is repetitively recorded in an unrecordedarea of AV file 1401, one VOB data must be distributively recorded on aplurality of portions, like VOB#3 1463, 1464, and 1465.

Information representing the physical recording position distribution ofrespective data distributively recorded in units of VOBs in single AVfile 1401 is allocation map table 1105 shown in FIG. 25. FIG. 29 showsthe information contents of allocation map table 1105 for the dataallocation in FIG. 28 used as an example. Allocation map table 1105consists of unrecorded area position distribution information 1621, anddata recording position distribution information 1622, 1623, and 1624 inunits of VOBs.

A set in which a link between successive LSNs is assured in each VOB isdefined as “extent”. In FIG. 28, data of VOB#3 is separately recorded asthree sets. In this example, since LSNs a+1 to b are linked assuccessive LSNS, this area constitutes “extent #γ 1473”. That is, theposition distribution where data of VOB#3 is recorded has tree extents#γ 1473, #δ 1474, and #ε 1475.

The number of extents 1601, 1602, 1603, and 1604 is recorded at thebeginning of the unrecorded area and position distribution informationabout each VOB in allocation map table 1105 shown in FIG. 29.Subsequently, start addresses 1606, 1607, 1608, 1609, 1610, and 1611 andextent sizes 1614, 1615, 1616, 1617, 1618, and 1619 are recorded. Thestart address is expressed by a “difference number” from the first LSNin AV file 1401. By expressing the start address by the differencenumber, information in allocation map table 1105 need not be changedwhen the whole contents of AV file 1401 are transferred to anotheroptical disc, resulting in high file transferability. In addition, asshown in FIG. 29, the extent size is expressed by the number of sectors.Instead of expressing the extent size as shown in FIG. 29, the extentsize may be expressed by the final address of the extent.

In the DVD-RAM disc standard, a physical address on optical disc 1001 iscalled a physical sector number (PSN), and all addresses used in thefile system are called logical sector numbers (LSNs), and an addressdefined on the file system in data area 1004 in FIG. 25 is called alogical block number (LBN). However, faithfully according to thisdescription, an explanation becomes complicated. For this reason, inFIGS. 28 and 29, the address is expressed by the logical sector numberfor the sake of simplicity.

The data structure of RTRW video manager information (RTRW_VMGI) 1021will be explained. RTRW video manager information (RTRW_VMGI) 1021 has,e.g., a data structure shown in FIG. 30, 31, or 32.

The data structure shown in FIG. 30 will be first explained. As shown inthe upper stage in FIG. 30, RTRW video manager information (RTRW_VMGI)1021 includes a video manager information management table (VMGI_MAT)and play list pointer table (PL_LPT). The video manager informationmanagement table (VMGI_MAT) includes a total of 512 byte data shown inthe middle stage in FIG. 30. This 512 byte data includes REP_PICTI.REP_PICTI includes data shown in the lower stage in FIG. 30.

Specific data in FIG. 30 will be explained briefly.

-   -   (RBP 149 to 163)REP_PICTI

Describes disc Representative Picture Information as follows.

Note: Setting and using this Disc Representative Picture Information isan optional function for both Recorders and players. Recorders whichdon't have capability to handle this information may set ‘FFH’ to all 15bytes of REP_PICTT. Players which don't have capability to handle thisinformation may simple ignore this information.

-   -   (RBP 149)PGCN

Describes the PGC number in which this Disc Representative Pictureexists. The Disc Representative Picture is specified as pointer in theoriginal PGC. So, when this picture pointer exists, set ‘0’ to PGCN.

-   -   (RBP 150)PGN

Describes the PG number in which this Disc Representative Pictureexists.

-   -   (RBP 151 to 152)CN

Describes the Cell number in which this Disc Representative Pictureexists.

-   -   (RBP 153 to 158)PICT_PT

Describes the Disc Representative Picture in the target Cell. When thispicture exists in a Movie Cell, PICT_PT describes the Presentation Time(PTM). When this picture exists in a Still Picture Cell, PICT_PTdescribes the Still Picture VOB Entry number (S_VOB_ENTN) in thecorresponding Still Picture VOB group (S_VOG) as follows.

The representative picture is extracted from these specific data.Instead, the VOB number may be used. The VOB number indicates a givenVOB (VOB number) in the disc.

The data structure shown in FIG. 31 will be explained. As shown in theupper stage in FIG. 31, RTRW video manager information (RTRW_VMGI) 1021includes a video manager information management table (VMGI_MAT) and aplay list pointer table (PL_LPT). As shown in the middle stage in FIG.31, the video manager information management table (VMGI_MAT) includes a12 byte (0 to 11) VMG identifier (VMG_ID), a 4 byte (12 to 15) endaddress of RTRWI (RTRWI_EA), a 4 byte (16 to 19) start address ofrepresentation picture VOBU (RPV_SA), a 1 byte (20 to 20) frame numberin representation picture VOBU (RIP_FN), a 7 byte (21 to 27) reserved, a4 byte (28 to 31) end address of VMGI (VMGI_EA), a 2 byte (32 to 33)version number of DVD RTRW video specification (VERN), and a 2,014 byte(34 to 2,047) reserved. A target representation picture (arepresentation picture is first I frame picture in VOBU) can beextracted from an address designated by the start address ofrepresentation picture VOBU (RPV_SA) and the flame number inrepresentation picture VOBU (RIP_FN).

The data structure shown in FIG. 32 will be explained. As shown in theupper stage in FIG. 32, RTRW video manager information (RTRW_VMGI) 1021includes a video manager information table (VMGI_MAT) and a play listpointer table (PL_LPT). As shown in the middle stage in FIG. 32, thevideo manager information management table (VMGI_MAT) includes a 12 byte(0 to 11) VMG identifier (VMG_ID), a 4 byte (12 to 15) end address ofRTRWI (RTRWI_EA), a 1 byte (16 to 16) program number in representativepicture (RPVOB_N), a 4 byte (27 to 20) time of representative picture inprogram (RP_ST), a 7 byte (21 to 27) reserved, a 4 byte (28 to 31) endaddress of VMGI (VMGI_EA), a 2 byte (32 to 33) version number of DVDRTRW video specification (VERN), and a 2,014 byte (34 to 2,047)reserved. A target representative picture can be extracted from a timedesignated by the program number in representative picture (RPVOB_N) andthe time of representative picture in program (RP_ST).

A target representative picture can be extracted from theabove-described data. The extracted representative picture is directlyprinted on the disc or label, or displayed as a preview representing therecording contents of the disc. Printing is basically the same asdescribed above with reference to FIG. 21.

<5> Contents of Original PGC Information (ORG_PGCI) 1024 and UserDefined PGC Information Table (ORG_PGCI) 1025

The contents of original PGC information (ORG_PGCI) 1024 and userdefined PGC information table (ORG_PGCI) 1025 will be described withreference to FIGS. 33 and 34. PGC control information 1103 in originalPGC information (ORG_PGCI) 1024 and user defined PGC information table(ORG_PGCI) 1025 has a data structure shown in FIG. 33, and the playbackorder is determined by the PGC and cell. The PGC is a unit for executinga series of playback processes which designate the playback order ofcells. The cell is a playback section of playback data in each VOB thatis designated by start and end addresses, as shown in FIG. 27.

PGC control information 1103 consists of PGC information managementinformation 1052, one or more search pointers of PGC information 1053and 1054, and PGC information 1055, 1056, and 1057.

PGC information management information 1052 includes number of PGCinformation indicating the number of PGCs. Each of search pointers ofPGC information 1053 and 1054 points the beginning of each PGCinformation to facilitate search. Each of PGC information 1055, 1056,and 1057 consists of PGC general information 1061, and one or more-cellplayback information 1062 and 1063. PGC general information 1061includes number of cell playback information serving as informationindicating the PGC playback time and the number of cells.

As shown in FIG. 34, playback data in the playback section from cell-Ato cell-F is designated in units of cells, and PGC information isdefined in each PGC.

(1) PGC#1 represents an example in which playback data consists of cellsdesignating a continuous playback section, and the playback order iscell-A→cell-B→cell-C.

(2) PGC#2 represents an example in which playback data consists of cellsdesignating a discontinuous playback section, and the playback order iscell-D→cell-E→cell-F.

(3) PGC#3 represents an example in which playback data can be skippinglyplayed back regardless of the playback direction and multiple playback,and the playback order is cell-E→cell-A→cell-D→cell-B→cell-E.

The aforementioned embodiment and modification have exemplified the RAMdisc, but the present invention is not limited to this. For example, thepresent invention may be applied to the ROM disc. The above embodimenthas exemplified the case in which the representative picture is a basepicture (I picture), but the present invention is not limited to this.For example, the representative picture may be a picture based on changedata representing a change (motion) in base picture.

Further, the above-described embodiment and modification have describedthe case in which the representative picture is printed based onrepresentative picture data, but the present invention is not limited tothis. For example, representative picture data may be stored in thememory (microcomputer block 30), and an icon may be generated from thestored representative picture data. The icon is generated bymicrocomputer block 30 and displayed on DVD video recorder display 48.In this manner, representative picture data can be used as a materialfor an icon.

1. An information reproducing method for reproducing a discrepresentative picture recorded on an information recording medium, saidinformation recording medium including, a managing file in whichmanagement information is stored, and a video file in which videoinformation is stored, wherein said video file is configured to store aplurality of video objects, said video objects including object units,each object unit including at least one of a video pack in which videodata is recorded and an audio pack in which audio data is recorded, saidmanagement information includes disc representative picture informationfor a disc representative picture, and a plurality of program chaininformation including cell information representing cells, at least oneof said program chain information designates respective cellreproduction orders, one of said cells refers to one of said videoobjects, said disc representative picture information includes firstinformation regarding a program chain number, a cell number, a picturepoint which describes time information for presenting said discrepresentative picture, and second information regarding a time whensaid disc representative picture information was made, and the programchain number is set to zero when the disc representative picture exists,but the second information regarding a time is set “FFh” when the discrepresentative picture does not exist, the information reproducingmethod comprising: reading said management information; referring tosaid disc representative picture information; and reading and decodingsaid disc representative picture.
 2. An information reproducingapparatus for reproducing a disc representative picture recorded on aninformation recording medium, said information recording mediumincluding, a managing file in which management information is stored,and a video file in which video information is stored, wherein saidvideo file is configured to store a plurality of video objects, saidvideo objects including object units, each object unit including atleast one of a video pack in which video data is recorded and an audiopack in which audio data is recorded, said management informationincludes, disc representative picture information for a discrepresentative picture, and a plurality of program chain informationincluding cell information representing cells, at least one of saidprogram chain information designates respective cell reproductionorders, one of said cells refers to one of said video objects, said discrepresentative picture information includes first information regardinga program chain number, a cell number, a picture point which describestime information for presenting said disc representative picture, andsecond information regarding a time when said disc representativepicture information was made, and the program chain number is set tozero when the disc representative picture exists, but the secondinformation regarding a time is set “FFh” when the disc representativepicture does not exist, the information reproducing apparatuscomprising: a first reproducer for reproducing said managementinformation, for referring to said disc representative pictureinformation, and a second reproducer and a decoder for reproducing anddecoding said disc representation picture.
 3. An information recordingmethod for recording a disc representative picture on an informationrecording medium, said information recording medium configured to store,a managing file in which management information is stored, and a videofile in which video information is stored, wherein said video file isconfigured to store a plurality of video objects, said video objectsincluding object units, each object unit including at least one of avideo pack in which video data is recorded and an audio pack in whichaudio data is recorded, said management information includes discrepresentative picture information for a disc representative picture,and a plurality of program chain information including cell informationrepresenting cells, at least one of said program chain informationdesignates respective cell reproduction orders, one of said cells refersto one of said video objects, said disc representative pictureinformation includes first information regarding a program chain number,a cell number, a picture point which describes time information forpresenting said disc representative picture, and second informationregarding a time when said disc representative picture information wasmade, and the program chain number is set to zero when the discrepresentative picture exists, but the second information regarding atime is set “FFh” when the disc representative picture does not exist,the information recording method comprising: generating said discrepresentative picture information; and recording said video file andsaid management information including said disc representative pictureinformation.
 4. An information recording apparatus for recording a discrepresentative picture on an information recording medium, saidinformation recording medium configured to store, a managing file inwhich management information is stored, and a video file in which videoinformation is stored, wherein said video file is configured to store aplurality of video objects, said video objects including object units,each object unit including at least one of a video pack in which videodata is recorded and an audio pack in which audio data is recorded, saidmanagement information includes disc representative picture informationfor a disc representative picture, and a plurality of program chaininformation including cell information representing cells, at least oneof said program chain information designates respective cellreproduction orders, one of said cells refers to one of said videoobjects, said disc representative picture information includes firstinformation regarding a program chain number, a cell number, a picturepoint which describes time information for presenting said discrepresentative picture, and second information regarding a time whensaid disc representative picture information was made, and the programchain number is set to zero when the disc representative picture exists,but the second information regarding a time is set “FFh” when the discrepresentative picture does not exist, the information recordingapparatus comprising: a first processor for generating said discrepresentative picture information; and a second processor for recordingsaid video file and said management information including said discrepresentative picture information.
 5. An information recording mediumconfigured to have data recorded thereon and data reproduced therefromby an information recording/reproducing apparatus, the informationrecording medium comprising: a pair of transparent substrates; anadhesive layer; a center hole going through the transparent substrates;a clamp area being located on an outer circumference side of the centerhole; a recording layer being provided on a surface of one of thetransparent substrates; a lead-in area being on the recording layer; adata area being located on the circumference side of the lead in areaand being on the recording layer; a first area, on the data area, beingconfigured to store a managing file including management information,and a second area, on the data area, being configured to store a videofile including video information, wherein said video file is configuredto store a plurality of video objects, said video objects includingobject units, each object unit including at least one of a video pack inwhich video data is recorded and an audio pack in which audio data isrecorded, said management information includes disc representativepicture information for a disc representative picture, and a pluralityof program chain information including cell information representingcells, at least one of said program chain information designatesrespective cell reproduction order, one of said cells refers to one ofsaid video objects, said disc representative picture informationincludes first information regarding a program chain number, a cellnumber, a picture point which describes time information for presentingsaid disc representative picture, and second information regarding atime when said disc representative picture information was made, and theprogram chain number is set to zero when the disc representative pictureexists, but the second information regarding a time is set “FFh” whenthe disc representative picture does not exist.